TH350C been sitting a few years

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scenic760

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The number you're looking to take off the piston for a 5 clutch mod is about .120 iirc in the th350 direct

So taking off about 1/8th of an inch? It's a cast aluminum part so I should be able to set up a jig and a carbide tip router would make short work of it I would think?

Also, makes perfect sense on the TC...it's probably like the washing machine when it gets out of balance and starts banging stuff around?!
 

scenic760

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I have a buddy that runs a auto repair shop. I use his brake lathe to cut pistons. Since brake lathes only cut .030 at a time, it does take awhile to cut the thickness of a clutch and steel.

Jake knows his stuff, that’s TH350 build description is how I set up my 350 builds. I can tell you from experience the dual feed modification won’t work on a TH350C. For whatever reason, the lockup won’t work. I have never researched the hydraulic diagrams to try and find out why. Just follow all the other steps and you will be fine.

I was googling around to see if anyone had any success on being able to dual feed a 350c and ran across this post on another forum:

The 350c can be dual fed but not thru the transfer plate as is done with a standard 350 because the auxilary valve body is in its place. Plug reverse passage in the case and leave out the center seal in the drum or middle ring on the pump cover.

It almost looked like it was a reply to a post of yours?! Is this what you tried and didn't work?

This was another answer from another forum:

You'll have to plug the reverse feed side of the direct clutch in the case. This is where the pump assembly mates to the case.Otherwise the converter will not lockup. Use a 5/16 cup plug and leave 4th sealing from the end off the stator support.
 
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Bextreme04

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I was googling around to see if anyone had any success on being able to dual feed a 350c and ran across this post on another forum:

The 350c can be dual fed but not thru the transfer plate as is done with a standard 350 because the auxilary valve body is in its place. Plug reverse passage in the case and leave out the center seal in the drum or middle ring on the pump cover.

It almost looked like it was a reply to a post of yours?! Is this what you tried and didn't work?

This was another answer from another forum:

You'll have to plug the reverse feed side of the direct clutch in the case. This is where the pump assembly mates to the case.Otherwise the converter will not lockup. Use a 5/16 cup plug and leave 4th sealing from the end off the stator support.

Interesting.. that is very similar to how you dual feed a 4L80E
 

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The 350C and standard 350 use a different transfer plate. You can dual feed a regular 350 by leaving off the middle large sealing ring off the pump, and/or leaving out the center seal from the drum. But it’s mandatory to block a hole in the case with a 3/8 set screw.

Shift kits dual feed by using a plate with a passage sandwiched between a filler plate and the stock transfer plate. The filler plate blocks off the hole that the setscrew would plug. The plate with the passage is used to dual feed the drum. The stock transfer plate keeps everything in position.

I didn’t bother researching why the converter wouldn’t lock, I reinstalled the seals and removed the set screw and it worked fine.

I just googled dual feeding a 350C, and one of the first hits that showed up was a thread I started years ago on yellowbullet. Seems evenly split as far as lockup converter working on a dual feed 350C. Maybe there were design changes or different case castings, different valve bodies, or just PFM (Pure ****ing magic ) as to why my converter didn’t lock. I guess it’s a roll of the dice.
 

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The th350 and 350C are basically the same, with the exception of the case, pump, valve body and forward clutch. Everything else s pretty much identical.

I’m not a professional rebuilder, but I have been working with most RWD Ford, mopar, and GM transmissions for about 20 years. I do build a lot of racing transmissions for friends, those twin turbo LS engines make a easy 1500hp. Seems like someone is always tearing something up!!
Ford you say

can you come donate your time to my e40d it likes to dump trans fluid if I put the torquey torque to the wheels. I let it rest and it seals back up. I can even provide the viton seal :)

jk lol I’m gonna do it one day.. I just have so little desire to do all that for one damn seal
 

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The 350C and standard 350 use a different transfer plate. You can dual feed a regular 350 by leaving off the middle large sealing ring off the pump, and/or leaving out the center seal from the drum. But it’s mandatory to block a hole in the case with a 3/8 set screw.

Shift kits dual feed by using a plate with a passage sandwiched between a filler plate and the stock transfer plate. The filler plate blocks off the hole that the setscrew would plug. The plate with the passage is used to dual feed the drum. The stock transfer plate keeps everything in position.

I didn’t bother researching why the converter wouldn’t lock, I reinstalled the seals and removed the set screw and it worked fine.

I just googled dual feeding a 350C, and one of the first hits that showed up was a thread I started years ago on yellowbullet. Seems evenly split as far as lockup converter working on a dual feed 350C. Maybe there were design changes or different case castings, different valve bodies, or just PFM (Pure ****ing magic ) as to why my converter didn’t lock. I guess it’s a roll of the dice.
Is there a way to manually engage the TCC like with a switch ain’t exactly practicld for everyday but someone who wants to get those mpgs on the highway or doesn’t mind the extra driver input could make use of that I think

wouldn’t be like a modern trans with 70% lock and all that jazz and auto disengages with brake etc but it would be more than a non lockup
 

scenic760

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The 350C and standard 350 use a different transfer plate. You can dual feed a regular 350 by leaving off the middle large sealing ring off the pump, and/or leaving out the center seal from the drum. But it’s mandatory to block a hole in the case with a 3/8 set screw.

Shift kits dual feed by using a plate with a passage sandwiched between a filler plate and the stock transfer plate. The filler plate blocks off the hole that the setscrew would plug. The plate with the passage is used to dual feed the drum. The stock transfer plate keeps everything in position.

I didn’t bother researching why the converter wouldn’t lock, I reinstalled the seals and removed the set screw and it worked fine.

I just googled dual feeding a 350C, and one of the first hits that showed up was a thread I started years ago on yellowbullet. Seems evenly split as far as lockup converter working on a dual feed 350C. Maybe there were design changes or different case castings, different valve bodies, or just PFM (Pure ****ing magic ) as to why my converter didn’t lock. I guess it’s a roll of the dice.

Hmmm.....you are probably correct that there was an ever so slight design change somewhere in the woodpile that will work on some and not on others...either that or the people who say you CAN dual feed it have no idea their converter never locked up, haha!
 

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Is there a way to manually engage the TCC like with a switch ain’t exactly practicld for everyday but someone who wants to get those mpgs on the highway or doesn’t mind the extra driver input could make use of that I think

wouldn’t be like a modern trans with 70% lock and all that jazz and auto disengages with brake etc but it would be more than a non lockup

The easiest way is to ground the negative wire of the solenoid, then use the positive wire on a toggle switch. Only problem is the converter will lock as soon as the trans shifts to 2nd gear (I think). If the pressure switch on the valve body is normally open, use that switch to provide the ground. As soon as the trans goes to 3rd gear, the pressure switch closes and provides the ground, locking the converter.

You could get fancy and wire the positive wire thru the brake switch. Apply the brakes, the switch opens, disengaging the converter.
 

Matt69olds

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Ford you say

can you come donate your time to my e40d it likes to dump trans fluid if I put the torquey torque to the wheels. I let it rest and it seals back up. I can even provide the viton seal :)

jk lol I’m gonna do it one day.. I just have so little desire to do all that for one damn seal


I have built lots of E4OD/4R100 transmissions. They are very similar to the Ford C6 with the addition of the overdrive clutch in the front of the trans. Other than being ridiculously heavy, and the typical Ford production changes, they aren’t too bad.

Remember the Ford advertising commercials stating “Quality is job one!”? I really think their motto is”let’s change things!”
 

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I have built lots of E4OD/4R100 transmissions. They are very similar to the Ford C6 with the addition of the overdrive clutch in the front of the trans. Other than being ridiculously heavy, and the typical Ford production changes, they aren’t too bad.

Remember the Ford advertising commercials stating “Quality is job one!”? I really think their motto is”let’s change things!”
I remember reading a **** load of TSBs from just the 90s to early 2000s and the shear amount of “this date to this production cut off” in reference to trans related stuff and most of it was e40d and I was like why is the pan entirely different and incompatible with a different type of gasket and how come you can convert it one way but not the other? Rubber vs molded o ring I believe. Maybe it was something else but I was like, whyyy
My first ford, an LTD had a fresh, but 20 year old, rebuild on a c6. Never had a single issue with that trans. Shifted nicely too, it would seemingly hang in 2nd too long but that breathtaking and exhilarating 150hp in 4500 pound car ran a little like poop and that poor anemic 2 barrel on a 400 was being asked a lot


It went 0-60 in the 18 seconds
 

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I just finished a C4 trans for a buddy with a 82 mustang. He is swapping in a really stout 351, so the “original” trans wasn’t going to make it.

I say “original” because it turns out the trans is a 69. Everything was going smooth until I tried to put the selling rings on the pump. They wouldn’t fit, they were too big in diameter, and too thick to fit in the ring groove. After doing some research, I found that Ford changed input shaft spline count (1st design, 22 spline on both ends, then a 22-26, and finally 26 splines on both ends) which resulted in design changes to both the pump abd the forward clutch housing. That meant his converter wouldn’t work. He bought a 71 core (checked the date codes this time) and everything went together ok.

I found out there is a case with and without provisions for a dipstick tube (some transmission have the full tube in the pan) cases with or without vents (some transmission use the case to vent, others have a vent in the extension housing) different valve body designs, different return springs in the clutch drums, different vacuum modulators, countless servo calibrations, the list goes on. And that’s just the C4!! There are lots of the same kind of production changes to the C6, the E4OD, AOD, etc. All these transmissions had a fairly long production life, it seems to me they could have easily perfected ONE design early in its life, and then kept it.

GM has a lot of stupid interchange problems as well, why different bellhousing bolt patterns? Internally/externally balance, different flywheel/water pump/ balancer combination, but nothing like Ford. I suppose if your around it for a long time you get use to it.
 

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I remember reading a **** load of TSBs from just the 90s to early 2000s and the shear amount of “this date to this production cut off” in reference to trans related stuff and most of it was e40d and I was like why is the pan entirely different and incompatible with a different type of gasket and how come you can convert it one way but not the other? Rubber vs molded o ring I believe. Maybe it was something else but I was like, whyyy
My first ford, an LTD had a fresh, but 20 year old, rebuild on a c6. Never had a single issue with that trans. Shifted nicely too, it would seemingly hang in 2nd too long but that breathtaking and exhilarating 150hp in 4500 pound car ran a little like poop and that poor anemic 2 barrel on a 400 was being asked a lot


It went 0-60 in the 18 seconds

When I was in highschool I had a 1980 Bronco with a 351M/C6 combo and it was a frickin tank. I was driving it down a steep hill near Mammoth in Eastern California and tried to put it into neutral at about 35mph, but of course my reverse lockout didn't work and I went to far and popped it into reverse.

It hesitated a second while my brain completely froze in an "oh ****" moment, then slammed into reverse and chirped the tires before the engine died and it kept coasting down the mountain. I had to almost stand on the brakes and muscle it to the side of the road. Got out expecting to see transmission carnage all over the place and found.... absolutely nothing. Looked like nothing had happened... so I got back in, turned the key, and it fired right back up. Put it in drive and it engaged just like normal and drove off without any hint that I had just tried to kill it. I then drove it down 395 back to the high desert and never had any issues with it.

It eventually got carjacked at gunpoint and led kern county deputies on a high speed chase before getting high centered on the fuel tank on a boulder in a creek bed and they shot it full of holes(true story... on my 18th birthday).
 

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When I was in highschool I had a 1980 Bronco with a 351M/C6 combo and it was a frickin tank. I was driving it down a steep hill near Mammoth in Eastern California and tried to put it into neutral at about 35mph, but of course my reverse lockout didn't work and I went to far and popped it into reverse.

It hesitated a second while my brain completely froze in an "oh ****" moment, then slammed into reverse and chirped the tires before the engine died and it kept coasting down the mountain. I had to almost stand on the brakes and muscle it to the side of the road. Got out expecting to see transmission carnage all over the place and found.... absolutely nothing. Looked like nothing had happened... so I got back in, turned the key, and it fired right back up. Put it in drive and it engaged just like normal and drove off without any hint that I had just tried to kill it. I then drove it down 395 back to the high desert and never had any issues with it.

It eventually got carjacked at gunpoint and led kern county deputies on a high speed chase before getting high centered on the fuel tank on a boulder in a creek bed and they shot it full of holes(true story... on my 18th birthday).

I guess OJ got wind of that and prompted him to make a run for it in his own Bronco eh? haha
 

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I guess OJ got wind of that and prompted him to make a run for it in his own Bronco eh? haha

Mine was post OJ... 2002 to be exact, but it was also a white Bronco!!
 

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When I was in highschool I had a 1980 Bronco with a 351M/C6 combo and it was a frickin tank. I was driving it down a steep hill near Mammoth in Eastern California and tried to put it into neutral at about 35mph, but of course my reverse lockout didn't work and I went to far and popped it into reverse.

It hesitated a second while my brain completely froze in an "oh ****" moment, then slammed into reverse and chirped the tires before the engine died and it kept coasting down the mountain. I had to almost stand on the brakes and muscle it to the side of the road. Got out expecting to see transmission carnage all over the place and found.... absolutely nothing. Looked like nothing had happened... so I got back in, turned the key, and it fired right back up. Put it in drive and it engaged just like normal and drove off without any hint that I had just tried to kill it. I then drove it down 395 back to the high desert and never had any issues with it.

It eventually got carjacked at gunpoint and led kern county deputies on a high speed chase before getting high centered on the fuel tank on a boulder in a creek bed and they shot it full of holes(true story... on my 18th birthday).
That’s adventurous. I have fun random stuff with my cars but none of them have involved a shootout yet

there’s always tomorrow

I mean, I’ve almost died twice in the driver seat of my park avenue but that wasn’t from GSW or anything
 

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