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HotRodPC
02-28-2011, 03:54 AM
As many of you were aware. I am building a TH350 for my brothers El Camino. I tore his core apart and didn't like a few things about his case, where it has been previously cut and shaved and weakening the bell housing area. So, I have to donate him one of my Th350 cores and this time, no longer in any kind of hurry, decided to take some pics and post up a thread that might be helpful to some of you.

This paticular core I bought for $20. You'll see later why I decided to buy it. It is a short tail shaft of 6in and appears to be a passenger car transmission but was taken out of a 70 Chevy Pickup.

http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1552&d=1298879674

HotRodPC
02-28-2011, 04:08 AM
When I purchased this transmission, it did not come with a trans pan. The guy used his pan on the transmission that he replaced and put back into his truck.

Normally, frist thing I like to do it tilt the transmisison to drain as much fluid as possible out of the transmission thru the tailshaft into a bucket or drainpan. Not necessary here since the pan had already been removed.

Next thing I like to do is remove all the externals of the transmission including tailshaft housing, governor cover, detent cable, vacuum modulator and accumulator cover.

Using a 9/16 socket remove the 4 tailshaft housing bolts.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1553&d=1298880499

Now is a good time to also remove the speedometer driver gear becasue the tailshaft isn't coming out of the case when you get to that part without the gear being removed. There is a speical tool made to remove this gear. I have been very fortunate to never need the tool, and always been able to get the gear off without damaging the gear. Some transmissions have a steel gear, and you will need the tool since its about like being pressed on and doesn't come off easily. You'll notice I use a small screwdriver to compress the keeper, then I use a much bigger screwdriver to tap the gear off with the palm of my hand, or a small hammer tapping it lightly not to damage the gear. And I do this closest to the output shaft as possible, where the gear has most of its meat and strength.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1554&d=1298880516

Here is what the output shaft, speedo gear and speedo gear retainer look like after being taken off.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1555&d=1298880529

HotRodPC
02-28-2011, 04:25 AM
Next, using a 1/2 socket or wrench, remove the bolt holding the vacuum modulator retainer in place. Once this bolt is removed, pull the modulator out of the case along with its O ring seal. Using needle nose pliers, pull the vacuum modulator vavle out of the case.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1556&d=1298881527

To removed the governor cover, use a screwdriver to pop the spring clip off the cover. Not pictured here because it was not included, but it's very simple to figure out without need of a pic. Then I use a medium sized flat screwdriver or chisel, and lightly tap around the cover, prying the cover out of the case. Notice here the seal that goes around the cover is not there, and some idiot used RTV silicone instead, making it tougher than normal to get the cover off. After the cover is removed, simply pull the governor out the case. Now is a good time to inspect the gear teeth for damage, and make the valve in the governor is moving freely. If not, you will need to acquire another governor for your build.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1557&d=1298881548

HotRodPC
02-28-2011, 04:37 AM
Fast forwarding a bit, since I did not get pics of the accumulator removal on the passenger side of the transmission, or the detent cable. The detent cable is easily removed with either a 3/8 or 7/16in socket depending on the size of the bolt used, I have seen both used, then pull the cable out, and disconnect its link from the detent cable link. Be sure to lay the cable somewhere out of the way, so it does not get damaged or kinked if you intend to reuse it. The accumular cover can be removed by inserting a pointed awl or pick into a side hole, then prying the snap ring out of the case. I'll be sure to show this process on assembly. Also note, the accumulator not being removed at this point will not keep the transmission from coming apart. So it can be taken out and inspected even after you have built the transmisison. You only remove it inspect the accumulator spring and replace the O ring, which is very rare to leak anyway.

HotRodPC
02-28-2011, 04:46 AM
Now with all the externals removed. Its time to roll the transmisison over, pan facing up. Remove the pan. As I said, this transmission did not have a pan on it when I bought it as a core. So you can see alot of dirt and debris on the valve body and filter. Now is also a good time to remove the filter using a wide blade standard screwdriver.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1558&d=1298882797


As I mentioned earlier, the reason I bought this transmission, is because I could tell by looking at the valve body that it had a shift kit installed in it. I knew this because I could see the gold valve body plate, and the transfer plate which a Turbo 350 needs to increase fluid pressure in the proper area of the transmssion. The shift kit alone if its the one I am thinking it is, is $35-$45 or so itself depending on where you get it. I assumed this was a B&M Shift Improver Kit, since B&M used gold color plates and TransGo usually used Black plates. If it was stock, it would not have had the transfer plate at all and used a standard steel seperator plate.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1559&d=1298882812

HotRodPC
02-28-2011, 04:58 AM
Next, I remove the spring loaded keeper pin to remove the detent lever and detent link that goes to the detent cable. Easily pryed out of its position using a medium size standard screwdriver.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1560&d=1298883437


This is what the detent lever, keeper pin and link look like after being removed.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1561&d=1298883456

Now down to the vavle body with the filter and detent components removed.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1562&d=1298883477

HotRodPC
02-28-2011, 05:08 AM
Next step will be to remove the valve body bolts and the vavle body from the case along with the manual valve that is linked with the S linkage to the manual vavle shift linkage.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1563&d=1298884075

This is what it will look like with the valve body removed.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1564&d=1298884098

Now is also a great time to pull the band servo out of the case with its pin and spring.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1565&d=1298884114

HotRodPC
02-28-2011, 05:27 AM
Now is the time I like to remove the keeper spring for the manual valve linkage. I do this now becuase I use a screwdriver to pry off of the the spacer support plate so I don't have to pry off the alluminum case itself, not to mention a much better angle before the spacer plate is removed. If you wish, you can also remove the rest of the linkage if you so choose. I chose not to. Many times you can rebuild a transmission without ever removing the manual linkage. However, I do remove it since I don't have a special tool to remove the linkage seal without removing the linkage itself. That tool is very useful if need to replace that seal while the transmission is still installed in the vehicle. I've never had the need for it, so I don't own one.

Prying up the spring loaded keeper.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1566&d=1298884935

Removed the spacer support plate bolts and removed the stock spacer plate. Now what you see if the transfer plate. Its quite obvious why this is called a transfer plate. You can see where fluid is tranfered from one place to another. A transmission without a shift kit, DOES NOT have the transfer plate, or the silver support plate underneath it.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1567&d=1298884959

Here is the 3 plates on top of the valve body spacer plate. The top plate is the only one used in a stock application. The gold and silver plates are part of the B&M Shift Improver Kit.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1568&d=1298884979

HotRodPC
02-28-2011, 05:49 AM
This is what the case looks like with the valve body plate removed. This plate also is part of the shift kit and why its gold. The valve body gaskets are also differant than stock vavle body gaskets. If I get a chance, I'll also post a pic of the stock plate and the B&M plate together later in the thread.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1569&d=1298886610

Also another sign a B&M shift improver kit has been installed, is that 2 check balls are not used. Notice the Red Arrows. Stock application requires check balls to be in those locations. With the shift kit, those balls are eliminated. The 2 blue arrows point to the other 2 check ball locations and they are present and used even with the shift kit. So keep that in mind. A Turbo 350 used 4 check balls for a stock OEM application.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1570&d=1298886619

Irishman999
02-28-2011, 05:53 AM
This is really neat, I am diggin this.

HotRodPC
02-28-2011, 06:02 AM
Now we are ready to remove the front pump. I failed to do so, but I usually recommend removing the front pump seal before removing the pump. Reason being, its much easier to remove the seal while its bolted into place in the transmission and held nicely. I also do not use any special seal remover tool. Its going in the trash anyway, so use a hammer and chisel and tear the seal away from the pump housing without damaging the housing itself. Its actually pretty easy to do without causing any harm.

Remove the pump bolts. You will see bolt holes that have a set of threads. This is for pump removal. You are supposed to use special tools similar to a dent puller to pull the pump out of the case. I have never used the special tools.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1571&d=1298887230
I made my own method using 3/8in all thread and wide shouldered jamb nuts to not damage the pump or the threads. Then I use large washers and a pry bar to pry off the case itself.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1572&d=1298887272

http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1573&d=1298887356

HotRodPC
02-28-2011, 06:13 AM
So for the first time ever, I am thinking my home made pump puller all thread tools are not going to work for me. After struggling with it, unlike usual, I look a little closer and realize, whatever Dilbert Dumbshit put this transmission together, used RTV on the pump too. All round the outer edge, and a solid bead around the front of the pump. So I cleaned what I could off with a razor knife, and had to do a little more improvising to my all thread tools to where I could pry a little harder and not damage anything. Finally, it worked and I got the pump off without doing any damage.. Thankfully !!!
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1574&d=1298887957
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1575&d=1298887987
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1576&d=1298888009

HotRodPC
02-28-2011, 06:24 AM
Sorry for the lousy out of focus pic here. I was still pissed off about the idiot who used RTV silicone on the front pump.

So this is what the transmission looks like with the front pump removed. Because the apply piston for the intermediate clutch pack is actually on the back side of the pump, what you see here is the intermediate clutch pack on the outer sprag race aka roller clutch.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1577&d=1298888640

This is the intermediate clutch pack removed from the case. Starting from left to right. The pressure plate, clutch, steel seperator, clutch, steel seperator, clutch, steel seperator, and finally wave spacer ring that the actual apply piston on the back of the pump engages with to apply this clutch pack.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1578&d=1298888658

Irishman999
02-28-2011, 06:30 AM
Have you ever tried using like a flat bar on the belhousing with the spinners on the outside of that?

The clutch pack is cool, it looks exactly like a motorcycle clutch and also the same design is used by Caterpillar for the brakes on their haul trucks.

HotRodPC
02-28-2011, 06:33 AM
So now that we have the intermediate clutch pack removed, what we are looking at is the direct clutch drum and the input shaft.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1579&d=1298889185
The input shaft is actually connected to the forward clutch drum which is behind the direct clutch drum. Those 2 drums will come out as 1 assembly, but first, you must remove the band. To remove the band, use a screwdriver to lift the band anchor over the case lugs that hold the band in its place. Once you do that, you should be able pull the band out of the case.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1580&d=1298889196

HotRodPC
02-28-2011, 06:37 AM
Have you ever tried using like a flat bar on the belhousing with the spinners on the outside of that?

The clutch pack is cool, it looks exactly like a motorcycle clutch and also the same design is used by Caterpillar for the breaks on their haul trucks.

I don't think I understand the question. I have only done it the way I have pictured because it works well and has alwasy worked for me until this idiot used RTV to glue the damn pump in the case which is not needed. No reason to use RTV on a transmission at all, unless you want to use it on the pan gasket which I have never done either, but I have seen that done before after a trans service to hold the gasket in place while putting the pan back on.

HotRodPC
02-28-2011, 06:45 AM
Now I pull the direct and forward clutch drums out as an assembly.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1581&d=1298889865

DOH !!! And to my suprise, we have broken parts and carnage !!! Not really !!! I expected to find this. I knew what was wrong with this transmission when I bought it. The input shaft was spinning with no resistance at all.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1582&d=1298889882
That told me the transmission had the 2nd most common failure of the Turbo 350. Broken input shaft and/or forward clutch drum where it mated to the input shaft, and sure enough I was right.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1583&d=1298889916

Irishman999
02-28-2011, 06:50 AM
I don't think I understand the question. I have only done it the way I have pictured because it works well and has alwasy worked for me until this idiot used RTV to glue the damn pump in the case which is not needed. No reason to use RTV on a transmission at all, unless you want to use it on the pan gasket which I have never done either, but I have seen that done before after a trans service to hold the gasket in place while putting the pan back on.

I drew a picture, if this makes any sense.

http://i640.photobucket.com/albums/uu130/irishman999/pumppuller.jpg

HotRodPC
02-28-2011, 06:56 AM
Now we are looking at the Front Planetary Ring gear insdie the sunshell. This will slide off by hand and remove it from the case.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1584&d=1298890442
Now we see the Front Planetary Gear Set along with another piece of the broken forward clutch drum. Very hard to see, but there is a small snap ring that holds that planetary to the output shaft. The snapring it about as big around as a quarter and its insdie the recess of the planet gearset, so its a real bitch to get off. I use 2 small screwdrivers and a pick to get it off. I say its unlikley you'd be able to get a pair of snap ring pliers inside the recess.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1585&d=1298890559

HotRodPC
02-28-2011, 07:02 AM
Now with the snapring removed, I can pull the front planetary gearset off the sungear.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1586&d=1298890883
And can also remove the Sunshell and sungear as a 1 piece assembly.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1587&d=1298890953

HotRodPC
02-28-2011, 07:09 AM
I drew a picture, if this makes any sense.

http://i640.photobucket.com/albums/uu130/irishman999/pumppuller.jpg

OK, so what you are saying then, is use some form or flat steel or even wood across the front of the bellhousing putting the allthread thru that, then tighten down the spinner nuts and use it as a puller. As you tighten the spinners it would pull the pump out of its case. I could do that, but I have never had to do so. It would work just fine though. I'd probably have to use longer allthread too. But, you get the idea. And you see, many of these "special tools" needed, can be improvised with and done without. Then of course, there are a few that just make sense to get becasue of the time and frustration they save. As you can tell, why do I need dent pullers to get a pump off? I've done many many transmissions with those pieces of allthread.

HotRodPC
02-28-2011, 07:20 AM
Now we are looking at the front side of the low/reverse clutch pack pressure plate and rear plantaries. I will pull the big snap ring out of the case, then I can grab the output shaft, and start pulling on it, to get the pressure plate to come out of the case after I remove the anti clunk spring.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1588&d=1298891916

After pulling on the output shaft, the rear plantetary gearset, and low/reverse clutch pack come out of the case. You will also notice one of the several thrust washers hanging on the front of the output shaft. Some thrurst washers are plastic type, and some are metal or brass type. Also sometimes torrington bearings are used in place of thrust washers. Thrust washers are what keeps parts from rubbing and grinding metal to metal giving a surface to ride on and against. Thrust washers are also important for keeping tolerances where they need to be.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1589&d=1298891966

HotRodPC
02-28-2011, 07:36 AM
After removing all of that. You might think you are done. But NO !!! What is left if the low/reverse apply piston.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1590&d=1298892852
This is where a special tool is required. Some builders will leave that piston in the case and start their build. Sure you can do it. But you are taking a risk because there are 3 square cut seals on that piston that may be dried out or hardened. Also if you take the case to be cleaned at a machine shop, those seals are now fried and for certain are no good. So if you want to chance it, do NOT take the case to be cleaned at the machine shop. Before I bought my special tool, I did make my own that worked OK. It had to do with a long bolt, and bent bracket, and I ran it thru the back of the case, with a large washer on it and a nut. As I tightened the nut, it compressed the springs but it didn't give me much room to get the snap ring out. So it worked, but it was very time consuming.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1591&d=1298892876
Once you have the snap ring taken out of its groove, you can release the tool and pull it out of the case, along with the springs and springs retainer.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1592&d=1298892895

HotRodPC
02-28-2011, 07:45 AM
Now the case is empty and completely disassembled and ready to go to the machine shop for a bath if you wish, or spray it down with some oven cleaner and take it to a high pressure car wash. All depends on how clean you want it, and how dirty it is. Do keep in mind, or reassembly, it is very critical to keep it clean.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1593&d=1298893363
Here you can see the 3 seals I was referring to. If these seals do not work, then you will not have manual 1st gear or reverse in your transmission, so they are quite important.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1594&d=1298893409

Although a poor pic, here is what the spring cage assembly looks like that holds the low/reverse clutch piston in place. These are the springs you are compressing with the special tool so you can remove the snap ring. This is one style. Another style is all the springs are seperate pieces with a flat ring that goes over the top of the springs. So when you take it out, you 1 flat ring, and about 20 loose springs that tend to go everywhere. Just like with anything, even the same trans model can have differant designs in parts depending on applications for use, or year model changes etc. Its always important to know what will interchange with what.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1595&d=1298893490

HotRodPC
02-28-2011, 07:58 AM
Here is what the output shaft looks like in a 2WD short shaft unit. It still has the rear ring gear attatched to it. Really no reason to remove it from the shaft unless you intend to change the shaft to a 9in shaft for a SB trans, or maybe you want to change out to a 4x4 output shaft. That would be the only real reasons to need to remove the ring gear from the shaft. Of course if the shaft was damaged and needed replaced, you'd also want to remove it from the ring gear and transfer the ring gear to the new shaft.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1596&d=1298894311
You'll notice the torrington bearing on the back of the ring gear riding on the output shaft. That is a selective bearing. Meaning it comes in differant thicknesses. You will select the correct size thickness to give you the correct tolerance in end play of your output shaft. Very rarely do you need to change that, but its a very critical step in your transmissions longevity.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1597&d=1298894332

HotRodPC
02-28-2011, 08:06 AM
Now to remove the rest of the manual valve linkage, which is pretty straight forward and easy to do. I don't think anyone would need pics for that. But after that, this one is ready for the machine shop to be cleaned. My machine shop usually charges me $20 to clean a case. Many times I can get them plenty clean at the car wash for about $2 and I don't have to wait 2 days to start building it if I do that.

So, stay tuned for the buld!!!! I am not yet sure yet, if I'll start another thread for the build, or if I'll just add to this thread. But is now after 6am and time for bed !!! :crazy::crazy: :roflbow:

oneluckypops
02-28-2011, 10:11 AM
Pretty good man pretty goo. If you dont mind I will add a few things.

First the pump, Hotrod used 2 3/8" allthread and some other stuff to pull these, I find it is simpler to simply take 2 3/8" Bolts and screw them in the same holes as PUSHER bolts. I have always done it this way with minimal effort, and I have NOT damaged any of the cases yet.

Second. It might help others if you can do your fancy arrows on the valve body side of the case To show where you can use compressed air to remove the LOW/Reverse piston. And I know this is build part but the same Whole you can use to air test the Low/Reverse clutch.

davbell22602
02-28-2011, 10:18 AM
:popcorn:

89Suburban
02-28-2011, 10:59 AM
Very well written Hotrod, and great points and additional tips from others here. I love it and read every word, but still can't comprehend all of it and am very intimidated by all these parts. Engine parts I am fine, but transmissions, it's a bit much for my brain.

oneluckypops
02-28-2011, 11:28 AM
Very well written Hotrod, and great points and additional tips from others here. I love it and read every word, but still can't comprehend all of it and am very intimidated by all these parts. Engine parts I am fine, but transmissions, it's a bit much for my brain.

Sorry to Hijack Hotrod please delete if you want.
I would reccomend to youto Find an Old TH350 And completely tear it down, DO NOT BUY ANY New Parts for it just yet.

After you get it torn down completely reverse the procedure and put it ALL back togather, Do that a few times till you think you have it figured out.

Once you get your "own" technique for installing the Lip seals and you feel confident in Dis assembly and reassambly go ahead and actually REbBUILD it.

Oh yea it would also help you to have an ATSG book handy

oneluckypops
02-28-2011, 11:30 AM
Now to remove the rest of the manual valve linkage, which is pretty straight forward and easy to do. I don't think anyone would need pics for that. But after that, this one is ready for the machine shop to be cleaned. My machine shop usually charges me $20 to clean a case. Many times I can get them plenty clean at the car wash for about $2 and I don't have to wait 2 days to start building it if I do that.

So, stay tuned for the buld!!!! I am not yet sure yet, if I'll start another thread for the build, or if I'll just add to this thread. But is now after 6am and time for bed !!! :crazy::crazy: :roflbow:

What about a parts inspection? Are you going to show them the proper ways of checking the worn bearings ect. ect. ect.?

89Suburban
02-28-2011, 11:40 AM
Sorry to Hijack Hotrod please delete if you want.
I would reccomend to youto Find an Old TH350 And completely tear it down, DO NOT BUY ANY New Parts for it just yet.

After you get it torn down completely reverse the procedure and put it ALL back togather, Do that a few times till you think you have it figured out.

Once you get your "own" technique for installing the Lip seals and you feel confident in Dis assembly and reassambly go ahead and actually REbBUILD it.

Oh yea it would also help you to have an ATSG book handyYup, hands on experience on a practice piece, that is on my wish list now. :High 5:

Old77
02-28-2011, 12:07 PM
Very interesting thread. I'm with 89Sub that it's very intimidating for some reason! I can do almost anything necessary under the hood but for some reason once it starts getting into the tranny I get very intimidated and the same is true when it comes to working on a diff. Maybe it has to do with the gears or something :shrug:

HotRodPC
02-28-2011, 12:28 PM
Oh hell Pops, I'm not deleting anything. Its here to add to too. Do you realize how long it takes to write up something like this? Look at my start and stop time. And I didn't take any breaks.
Fact of the matter is, I skipped alot of stuff jus because its almost impossible to include everthing.
I almost disagree about buying ATSG manuals for newbies. I mean, go ahead and get them, cuz eventually your intent is to be a trans builder and the books are good. But, ATSG manuals are intended for the Transmission Professional, not a newbie, and do not go into detail about many things since its assumed you have basic trans knowledge already. What I do highly recommend for a newbie, is to read the Ron Sesssions TH350 Handbook from beggining to end before you even crack one open. You may not even understand some of it, but read it anyway. Then when you do get to crack one open, some of what you read will already makes sense, then it will come to you. Then when you start your tear down, have the book with you and start going thru it again. Its also about half price of an ATSG manual.
http://www.amazon.com/Turbo-Hydra-Matic-350-Handbook-Sessions/dp/0895860511/ref=sr_1_1?ie=UTF8&qid=1298909811&sr=8-1

As far as 89S and still not being able to comprehend, don't expect to comprehend it until you start tearing one apart. And if you think this is alot of parts??? Just hold onto your socks brah, cuz all this was is just disassembly. You can easily triple or quadruple these parts once you start tearing down the pump to rebuild it, the valve body to go thru it, and each one of the drums have to be taken apart and seals replaced, and pistons cleaned, pressure plates, steels and clutches to inspect clean and replace along with retainers. I also didn't show hardly any thrust washers or bushings that need inspected, measured and replaced if needed, and sometimes replaced just because. What you see here 89S, isn't half of it, and if you think I'm even kidding, ask Pops. I'm sure he'll agree. All I did here was touch the surface.
Also as Pops points out, his way of removing the pump. That goes without saying. Every builder uses different techniques that they have learned by, or figured out on their own. So there really is no wrong way or right way, provided you don't tear anything up, and the end result is a properly functioning transmission.

HotRodPC
02-28-2011, 12:40 PM
And BTW, as far as learning to build a transmisison, I recommend everyone start with a Turbo 350. The only thing simplier to build is a Powerglide. If you can build a Th350, then you can also build a Powerglide. Once you get the TH350 down pretty good, or at least one good one under your belt, do a TH400. A TH400 is just a tad bit more complicated in some areas, a bit easier in others, but the point is, they are differant as night and day, so you'll learn how to adapt basic trans building skills between differant models. A TH400 has a center support, a TH350 does not. First thing you see opening up a T350 if your Intermediate clutches. You don't see intermediate clutches on a TH400 til you get to the center of the transmission. I also have a TH400 build thread too, so you might look at that, and you can see the differences and compare the 2, then you'll know what I am talking about.

davbell22602
02-28-2011, 12:45 PM
Oh hell Pops, I'm not deleting anything. Its here to add to too. Do you realize how long it takes to write up something like this? Look at my start and stop time. And I didn't take any breaks.
Fact of the matter is, I skipped alot of stuff jus because its almost impossible to include everthing.
I almost disagree about buying ATSG manuals for newbies. I mean, go ahead and get them, cuz eventually your intent is to be a trans builder and the books are good. But, ATSG manuals are intended for the Transmission Professional, not a newbie, and do not go into detail about many things since its assumed you have basic trans knowledge already. What I do highly recommend for a newbie, is to read the Ron Sesssions TH350 Handbook from beggining to end before you even crack one open. You may not even understand some of it, but read it anyway. Then when you do get to crack one open, some of what you read will already makes sense, then it will come to you. Then when you start your tear down, have the book with you and start going thru it again. Its also about half price of an ATSG manual.
http://www.amazon.com/Turbo-Hydra-Matic-350-Handbook-Sessions/dp/0895860511/ref=sr_1_1?ie=UTF8&qid=1298909811&sr=8-1

As far as 89S and still not being able to comprehend, don't expect to comprehend it until you start tearing one apart. And if you think this is alot of parts??? Just hold onto your socks brah, cuz all this was is just disassembly. You can easily triple or quadruple these parts once you start tearing down the pump to rebuild it, the valve body to go thru it, and each one of the drums have to be taken apart and seals replaced, and pistons cleaned, pressure plates, steels and clutches to inspect clean and replace along with retainers. I also didn't show hardly any thrust washers or bushings that need inspected, measured and replaced if needed, and sometimes replaced just because. What you see here 89S, isn't half of it, and if you think I'm even kidding, ask Pops. I'm sure he'll agree. All I did here was touch the surface.
Also as Pops points out, his way of removing the pump. That goes without saying. Every builder uses different techniques that they have learned by, or figured out on their own. So there really is no wrong way or right way, provided you don't tear anything up, and the end result is a properly functioning transmission.

I'm gonna buy that book eventually.

89Suburban
02-28-2011, 12:47 PM
How about the 700r4?

HotRodPC
02-28-2011, 12:47 PM
What about a parts inspection? Are you going to show them the proper ways of checking the worn bearings ect. ect. ect.?

Noway man. I just did all this work here to tease them a bit. If they want to see the build, tear down and inspection process, they'll have to buy my HotRodPC Productions DVD. Teardown, Inspection and Building of the TH350.
$39.95 + $9.95 shipping. But wait, there's more. Order now and you receive a FREE autographed by HotRodPC, poster of a TH350 Exploded View. Only availalble while supplies last.

davbell22602
02-28-2011, 12:48 PM
And BTW, as far as learning to build a transmisison, I recommend everyone start with a Turbo 350. The only thing simplier to build is a Powerglide. If you can build a Th350, then you can also build a Powerglide. Once you get the TH350 down pretty good, or at least one good one under your belt, do a TH400. A TH400 is just a tad bit more complicated in some areas, a bit easier in others, but the point is, they are differant as night and day, so you'll learn how to adapt basic trans building skills between differant models. A TH400 has a center support, a TH350 does not. First thing you see opening up a T350 if your Intermediate clutches. You don't see intermediate clutches on a TH400 til you get to the center of the transmission. I also have a TH400 build thread too, so you might look at that, and you can see the differences and compare the 2, then you'll know what I am talking about.


What about a 700r4? I have that one thats toast in the 88 1500. I have this book http://www.cartechbooks.com/vstore/showdetl.cfm?DID=6&Product_ID=3697&CATID=3

davbell22602
02-28-2011, 12:50 PM
Noway man. I just did all this work here to tease them a bit. If they want to see the build, tear down and inspection process, they'll have to buy my HotRodPC Productions DVD. Teardown, Inspection and Building of the TH350.
$39.95 + $9.95 shipping. But wait, there's more. Order now and you receive a FREE autographed by HotRodPC, poster of a TH350 Exploded View. Only availalble while supplies last.

:happy175:

HotRodPC
02-28-2011, 12:57 PM
How about the 700r4?

What about it??? That's even more complicated. That DVD is $59.95 + $9.95 shipping, and you don't get shit with it. No autographed Exploded View Poster. That's an additional $14.95. :happy175:

89Suburban
02-28-2011, 01:43 PM
What about it??? That's even more complicated. That DVD is $59.95 + $9.95 shipping, and you don't get shit with it. No autographed Exploded View Poster. That's an additional $14.95. :happy175::sad72:

Swims350
02-28-2011, 01:58 PM
awesome, I needed pics and info, I need to swap the guts out of mine to another case since a chunk of mine is gone. I glued it up and it's not leaking, but never know when it might come back or something.

HotRodPC
02-28-2011, 02:15 PM
awesome, I needed pics and info, I need to swap the guts out of mine to another case since a chunk of mine is gone. I glued it up and it's not leaking, but never know when it might come back or something.

Yep, if you are doing a guts swap and that's all, then this info here is all you need. And if you are certain your donor is good for the low reverse, then you don't even need to pull that piston. Be carefull with your paper gaskets like the valve body and front pump, you can reuse them if you don't tear them. Just be sure to use a torque wrench and torque your bolts to spec. I usually use an inch lb torque wrench. So if it calls for 12ft lbs. Then 12 x 12in = 144 and I'd torque to 150 in. lbs. 6in lbs tighter will not hurt a thing.

Swims350
02-28-2011, 04:55 PM
I do the same thing. As for gaskets that is what I thought, although I may buy a gasket and seal kit to be sure if I tear anything.

I know the parts/guts I am going to use are good, they are in my 88 and we drive it alot, but the case around the PS cover for the 1-2 accumulator the back end if broke off and leaked. I used some seal all glue on it and seems to have done the truck.

If it starts to leak or I just have the time and want something to do I am going to switch cases, the case is good, came from dad's 84 but the internals suck. it was acting like driving with the brakes on, not really slipping like in neutral just acting like it was loading the motor and revving but not transferring the power. So it's a donor parts trans now.



Another point I was going to make, that musty be the stage one shift kit/HD version since it has 2 check balls left in place. I've put in 2 of those kits and did the stage 2 street/strip version both times, uses the same stacked plate setup but only one check ball. The stage one involves removing the spring from the 1-2 acc. on the side cover too. I never did that one.

HotRodPC
02-28-2011, 06:41 PM
I do the same thing. As for gaskets that is what I thought, although I may buy a gasket and seal kit to be sure if I tear anything.

I know the parts/guts I am going to use are good, they are in my 88 and we drive it alot, but the case around the PS cover for the 1-2 accumulator the back end if broke off and leaked. I used some seal all glue on it and seems to have done the truck.

If it starts to leak or I just have the time and want something to do I am going to switch cases, the case is good, came from dad's 84 but the internals suck. it was acting like driving with the brakes on, not really slipping like in neutral just acting like it was loading the motor and revving but not transferring the power. So it's a donor parts trans now.



Another point I was going to make, that musty be the stage one shift kit/HD version since it has 2 check balls left in place. I've put in 2 of those kits and did the stage 2 street/strip version both times, uses the same stacked plate setup but only one check ball. The stage one involves removing the spring from the 1-2 acc. on the side cover too. I never did that one.

This one didn't have the accumulator spring either for some reason, but yes, its the Stage 1 RV/Heavy Duty Kit. I have done many Stage 2 Kits, and I love the way they work on the T350. I had a guy once, punch me out 100 of those transfer plates. It was like $100 set up fee, then after that, it was like $1.25 per plate. So I had about $2.25 in each plate, threw away check balls and srprings, and then used a paper hole punch to enlarge 3 or 4 holes in the stock paper valve body gaskets and there I had it. It was a HRPC Shift Kit. I charged the same price as store cost as a B&M shift kit back then. Those were the days, I was making some cash back then.

Swims350
02-28-2011, 07:25 PM
the spring is removed because of the stage one kit. The instructions call for it, but stage 2 doesn't never understood that one.

That's all the stage 2 kits are, the plates, remove all balls but one, then the gaskets they have, plus enlarging like one hole in the seperator plate.

HotRodPC
03-01-2011, 12:16 AM
the spring is removed because of the stage one kit. The instructions call for it, but stage 2 doesn't never understood that one.

That's all the stage 2 kits are, the plates, remove all balls but one, then the gaskets they have, plus enlarging like one hole in the seperator plate.

You sure about that on the accumulator spring? I never installed it on Stage 2 kits either. Might be why my Stage 2 kits worked better than everyone elses. :shrug: All the accumulater is for is to cushion the 1-2 shift, so by eliminating it, you are going to have a harsh firm 1-2 shift which is the purpose of a shift kit, so I never reinstalled the accumulator srping unless it was a stock granny rebuild.

HotRodPC
03-01-2011, 03:48 AM
Next up !!! Coming Soon to a thread near you !!!


Trans Rebuild Kit including, Steels, Clutches, Seals, Gaskets, Filter, Band, Check Balls and Metal Clad Sealing Rings !!!
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1607&d=1298965657

Raysbestos Clutches, Made in USA !!! No Junk in Transmissions I build !!!
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1608&d=1298965682

Heavy Duty Kevlar Band. More holding power !!! Also Made in USA !!!
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1609&d=1298965696

TransJel Assembly Lube. One of the few brands. I like this brand. Probably nothing more than Vaseline mixed with Transmisson Fluid. Very Important to use a lube that will melt down and become part of the transmission fluid. This is why you don't use lube like White Lithium Grease to build a transmission.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1606&stc=1&d=1298965613

Swims350
03-01-2011, 10:14 AM
yep, posative on it. The stage 1 rv/hd mode you remove it from the side cover.

stage 2 you leave it.

It confused me because I always heard what you said, remove it and get a harder or faster shift. I was going to remove it, but figured since the instructions said not to I'd leave it alone.
I loved all my stage 2 kits, it would hit 2nd good and get a really nice and long tire chirp, then sometimes going to 3rd would get a little one. That's just in the monte carlo with 3.42's and 215/65's on it. The 2k stall converter held it back too, or was bad, with a stock one if you get on it hard and with a 305 it'll almost let loose going from 1 into 2. it really slips tires.

Godd info though next time I'll remove the spring. May do it on my 4x4. Guy who built it said he removed all but one bb and it should firm up the shifts etc. well it's fast, no slippage but not firm like a shift kit. I doubt he did any plate work though to the stacked plates or the seperator.

HotRodPC
03-01-2011, 10:41 AM
I just read the B&M Instruction sheet and you are right. It clearly says, Heavy Duty Only, Use an Awl or small and pry out .......

So that must be why my Stage 2 Kits were wicked as hell. I'm telling you, drag racers loved my Stage 2 kits. They say it works as well as a Full Manual Valve Body without being Full Manual valve body. Cars with LSD, with a mid throttle take off from a light, not even really getting on it hard, would get sideways hitting 2nd gear. I knew the 1 and 2 check balls, 2 for HD and 1 for SS. I also confirmed the plate was drilled for HD on this one. So its a Stage 1 Kit. I'll save it for one of my builds in one of the trucks if I ever used a T350 again. So far seems 2 are going to be Th400 and 2 are going to be 700r4.

HotRodPC
03-01-2011, 10:59 AM
Next up !!! Coming Soon to a thread near you !!!


Trans Rebuild Kit including, Steels, Clutches, Seals, Gaskets, Filter, Band, Check Balls and Metal Clad Sealing Rings !!!
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1607&d=1298965657

Raysbestos Clutches, Made in USA !!! No Junk in Transmissions I build !!!
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1608&d=1298965682

Heavy Duty Kevlar Band. More holding power !!! Also Made in USA !!!
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1609&d=1298965696

TransJel Assembly Lube. One of the few brands. I like this brand. Probably nothing more than Vaseline mixed with Transmisson Fluid. Very Important to use a lube that will melt down and become part of the transmission fluid. This is why you don't use lube like White Lithium Grease to build a transmission.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1606&stc=1&d=1298965613

You know things are getting bad when, you start doing trailer previews for threads to come in the future. :roflbow::roflbow::roflbow: :shitsweak:

Swims350
03-01-2011, 12:01 PM
shoot if you removed the spring for the S/S mode, that's what I'm going to do.

I had heard others say you can drill out the 2 holes for the HD kit, then drill out the 3rd. which is for the S/S kit, so maybe I'll look into that, drill the holes, remove the spring and do the stage 2 or whatever.

oneluckypops
03-03-2011, 12:37 AM
you ever gonna build this tranny? I want my peakctures

HotRodPC
03-03-2011, 01:02 AM
Yeah, in fact tonight, I finished taking off the accumulator and pressure taps, so I have more pics to add to the disassembly. Normally I do that first, but didn't this time.

Oh yeah, you're wanting pics of the Haggery Snapress. I'll just do that now too since I'll be downloading these accumulator pics. I'll have to fire up the other computer though. I am in the living room tonight on the house guest computer. I keep all my pics on my main computer in the office. So give me a bit, to get the pics, then I'll change computers. I'll have them up tonight.

HotRodPC
03-03-2011, 01:03 AM
I want my peakctures

Hey wait a minute. I want My 79 Blue 4x4 gear shifter truck too dammit !!! :Sumo:

http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1707&d=1299136670

oneluckypops
03-03-2011, 01:06 AM
Yeah, in fact tonight, I finished taking off the accumulator and pressure taps, so I have more pics to add to the disassembly. Normally I do that first, but didn't this time.

Oh yeah, you're wanting pics of the Haggery Snapress. I'll just do that now too since I'll be downloading these accumulator pics. I'll have to fire up the other computer though. I am in the living room tonight on the house guest computer. I keep all my pics on my main computer in the office. So give me a bit, to get the pics, then I'll change computers. I'll have them up tonight.

:tictoc:

HotRodPC
03-03-2011, 01:18 AM
:tictoc:

:Moon: and your ticktock !!! I got the pics. Now I have to go get on the computer to post up. I also have to resize them, so it will take me just a bit, but they should be up tonight. I'll probably put them in a seperate thread incase someone else wants to try to make one too.

89Suburban
03-03-2011, 01:49 AM
:popcorn:

HotRodPC
03-03-2011, 02:27 AM
OK, so normally, I'd remove the accumulator cover, spring and piston when I remove the external components but I didn't have my pic handy. So I have now done it.

Insert the pic in the side hole pushing the snap ring out of the groove so you can get a screwdriver behind it, and pry it out of its position.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1699&d=1299133514

Now, using some kind of tool you can grap the accumulator cover and pull the cover out.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1700&d=1299133544

Normally, you'd see a big spring in here. But because this transmission had a shift kit, the accumulator spring has been discarded. Purpose of the spring and accumulator is to cushion the 1-2 shift. Being a shift kits intent is to firm up the shift, the spring is eliminated.

Now pretend its you favorite girl and give it a 2 finger inserstion to pull the accumulaor piston out as far as possible by hand, then grab it with pliers or other tool and pull it out of the case.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1701&d=1299133585
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1702&d=1299133616

Here is the accumulator cover, piston, O ring and snap ring removed from the case. Notice to the 2 sealing rings on the accumulator piston. Those ger replaced in a rebuild as well as the sealing O ring to the cover.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1706&d=1299134230

HotRodPC
03-03-2011, 02:33 AM
Also, remove the 3 pressure tap plugs. This is not always necessary, but a good idea so that you can run some air thru the tap ports in the event some debris has been trapped in the ports. These ports are only used for transmssion testing and diagnotics.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1703&d=1299133931

This is what the pressure tap plugs look like out of the case.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1704&d=1299133974

Here is what this side of the case looks like with pressure taps and accumulator removed. This case is now 100% stripped and ready for cleaning and rebuilding at this point.
http://www.gmsquarebody.com/forum/attachment.php?attachmentid=1705&d=1299133991

Swims350
03-03-2011, 12:37 PM
hey hrpc, what does one use to block movement of that 1-2 piston once removed? I heard over and over to block it's movement when you remove the spring.

Also I hear alot of the time you can get the codes off the cover to tell you more info on the trans, kind of like an engine suffix, but then again I hear most shops have buckets of them and just throw on whatever and don't keep them matching the original trans.

That hole for the pick, that's where my case is broke, it goes up about 3/4 inch above the hole with a crack and barely hanging on, then the lower section including the hole is just gone. I can't beleive the SOB built it for us and didn't do anything with it, like change cases or something.

89Suburban
03-03-2011, 01:14 PM
@ swims - That sucks!

@ HRPC - Great pics and step by steps! :waytogo:

HotRodPC
03-03-2011, 01:37 PM
hey hrpc, what does one use to block movement of that 1-2 piston once removed? I heard over and over to block it's movement when you remove the spring.

Also I hear alot of the time you can get the codes off the cover to tell you more info on the trans, kind of like an engine suffix, but then again I hear most shops have buckets of them and just throw on whatever and don't keep them matching the original trans.

That hole for the pick, that's where my case is broke, it goes up about 3/4 inch above the hole with a crack and barely hanging on, then the lower section including the hole is just gone. I can't beleive the SOB built it for us and didn't do anything with it, like change cases or something.

On the 350 I don't know that you need to block the accumulator piston from moving. Some models because the accumulator is actually in the pan near or under valvebody. In those cases some special tools are used to hold it in place, sometimes there is a C clip that hold it onto a pin etc, just different varietes of accumulators. This 1-2 accumulator isn't one of those.

Also yes, SOME year models have #'s stamped on the acc cover, some other trans models have #'s stamped on the acc cover. This paticular trans does not.

That sucks he built yours that way. That's the difference in builders pride in their work. I am using a differant case for this build. The ears on the bell housing of this trans had been cut off. Sometimes necessary if you are putting a trans in tight quarters like Tbucket build for example. But this is in an El Camino with headers so someone may have cut it off to be able to install the trans without removing the headers which was stupid. It weakens the bell housing. One side they got real close to a bolt hole and it appears to me it has a light fracture or could easily fracture and break. So, I told my bro I wouldn't build his trans. Being the good guy I am, I ended up donating him a donor trans core which is why this disassembly didn't have the pan or good detenct cable on it. The case is rock solid though. So are the hard parts other than the broken drum and input shaft. I only spent $20 on the core and I knew it had a $40 shift improver kit, so I'm keeping than for later build of my own. Its drilled for Stage 1 RV/Heavy Duty.

Swims350
03-03-2011, 07:15 PM
what part did they cut off I didn't even notice.

HotRodPC
03-22-2011, 07:39 PM
what part did they cut off I didn't even notice.

I missed this post swims. They had trimmed the flanges on both sides of the bellhousing. Sometimes common to make a trans fit in a smaller 4 cylinder car that has been V8'ed or many times in like kit cars or T bucket projects where space is very limited. It does weaken the structure of the bell housing a bit, but for a light car, its probably not an issue. I prefer not to use those kind of cut cases when I can get away with it. This paticular tear down is going in an El Camino, so space is not an issue.

Swims350
03-22-2011, 09:09 PM
oh ok I know what you mean now. Yea the headers for the MC hit that flange, right around the starter kickout part of the flange, I left it alone, they fit and bolted up but were right on that flange.

zcampbell
05-30-2012, 01:05 AM
Hey im in the middle of my first TH350 disassembly and have got it down to the manual 1st and reverse clutch pack but can't seem to remove the ring holding it in. Any special trick to that or am I an idiot?

Very nice job with the step by step. I had no trouble disassembling and understand this trans thanks to this post.

HotRodPC
05-30-2012, 01:47 AM
Now when you say ring, do you mean the snap ring? That one is pretty easy. Actually the easiest one to get normally. So that actually makes me think you're reffering to the pressure plate behind the snap ring. The pressure plate can be a bit challenging for 2 reasons. #1, the anti cluck spring holds pressure on it. #2, sometimes that pressure plate rocks in the case and chews on the case lugs, then the pressure plate sits behind the chewed on lugs. So to get it out sometimes, you have to figure out a way to work it back to where the lugs line up with the pressure plate, then it should come free with a little persuasion.

82chevy350
11-24-2012, 12:06 PM
Im about to have to do this so my trans dont take a dump on me once i get my 383 finished.. You make it look so easy haha

HotRodPC
11-24-2012, 12:12 PM
Th350's are easy. Just with any trans. Lots of patience so you don't tear or fold over lip seals, get in a hurry and leave out thrust washers, torrington bearings or snap rings and all should be well. Making sure you check end shaft plays should tell you you if you have forgotten thrust washers and some snap rings, air checks should tell you if you tore any lip seals.

82chevy350
11-24-2012, 12:33 PM
ill defiantly be referring to this thread when i do!

WVscottsdale
12-16-2012, 12:42 AM
Where did you get the special tool from for the low reverse piston

HotRodPC
12-16-2012, 02:20 AM
I bought it at a Transmisison Parts supply store. You can also buy them on eBay. For my first few transmissions, I used a homemade tool out of a long bolt, with washers and nut. May have even been a piece of all-thread. It was slow and bulky, but for a 1 time use if you're not going to be building transmissions often, save your money. They're not cheap now days.