th350 case advise

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Tyger13us

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Hey all,,
ive got my th350 tore down finally, and in an inspection i had a bitch of a time getting the low/reverse pressure plate out of it

It would seem the the pressure plate has eaten in to the case and it wouldnt slide out..

i had to work on it with picks and mini screwdrivers and pushing the tail shaft to get it to spin/slide sideways to clear the upper lip in the case...

ive never had problem like this before? in other 350's ive had.......

so? how bad is the case? and should i replace it? or maybe get a center support out of a 700r4?
or get a case saver.......

I know nothing of this trans,, it was in the truck when i bought it and was freshly rebuilt..so the guy said,, it looks it too,, all the guts and clutches look new and good..

the band shed-ed its surface and fell down into the pan and partly blocking the pickup screen...

so i kinda figured who ever rebuilt it just tossed in a used band and said good enough for who its for..

it wasnt right and i could feel it when i drove it, so it got parked until i could get to a tear down..
didnt want to burn it up, there is no one in 100 miles in any direction to get a tow home....

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Matt69olds

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Go to your nearest transmission shop, and ask them to order a TH350 case saver. It’s a piece of solid steel in the shape of the anti clunk spring. It’s a few bucks and will save a other wise junk case. If your going to really beat up on the trans, or have big tired and lots of power, the make a bolt in low roller clutch housing. I have never installed on personally, but I have seen them. Another upgrade to consider is replacing the TH350 roller clutch with the same part from a 700R4. It has much bigger rollers.

There are a few other low buck durability tips if your interested.
 

Jason Deckard

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Yea whoever was inside it last didnt put the anti clunk spring back in. I have several 350 cases if you need one
 

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Install one of these with a case saver. I just did one in a buddies 77 Corvette that looked like that, so far so good.
 

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I have never used one, I have seen them. How much do those bolt in sprags run? I assume the use the 700 sprag?
 

Irishman999

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I have never used one, I have seen them. How much do those bolt in sprags run? I assume the use the 700 sprag?
They are around 100 bucks through transtar. You can upgrade to a wider 4l60 sprag.
 

Jason Deckard

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I would try to find a new case. I have several if you need one
 

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Thanks Guys,, yea,, been looking into one of the bolt in kind like Irishman showed.......
i was looking in to the 4 little mettle piece ones also?
but in the back of my head,, i keep getting??,,,, they maybe ok in a grocery getter car,, but not work to well in a 450ish hp k10 4x4-205 t case and decent31x10.5 tires & locker......
I already rounded up a core t-350 i had,, the guy said it was just gone through..
yea,, it was.. lots of good parts,,
but the 1st-R inner race was exploded,,lol,,rollers everywhere,, jacked up the lower planets and sun shell.....
that case has also the revers to drive worn case lugs.......
i have 3 other t-350's, but they need to be pulled, and considering its the middle of F*ing winter...

we got over a foot of wet nasty snow the other day,, yesterday it all melted,, so its all swamp land in the desert..
went to order some parts? only to find out some hacked my card and they put a block on it..
Sigh,, so now im waiting for a card in the mail, when ever the F it shows up.....

And when it dont rain,, it POORS!!
my only driver,, 82 c10 diesel ether has a cracked head or a bad head gasket..
No water in anything,, oil/exhaust/ground.. but when its running cylinder pressure is pumped in to the cooling system...
so the radiator blows bubbles now, out the over flow......

i spent the last 2 weeks fixing an 85 ford f150,, so id dont have to ******* walk...
but since all the damn snow melted and another big storm coming from calif?
wont be going anywhere for awhile,, if i stick that ford in the mud wont get it dug out till spring some time..

Just for ***** and gigles,, i have a wide bushing the direct drum,, double bushings for the sun gear..
a set of slightly used red clutches,, look like new never used,, a red band,, trans go 1&2 kit that was already installed for the double presure trick for the direct drum with the plate....

But i do have a question? never seen it before? at least in any trans ive built,,
what takes out the direct drum clutches?
ether the dude before me run it out of oil,, or it was towed without puting the T-case in neutral..
any way,, thats why it got tore down,, the band lost its lining and the direct drum clutches are mettle to mettle......
the trans oil was clean and ***** pink,, nothing in the pan except for the Band lining laying on top of the filter pluging it up.
but all in all,, everything else in the trans look like it was new rebuilt,, all the other clutches look new also,, even Mic out as new..
ive seen burnt up t350's before,, OMG didnt even want to rebuild one that bad,,lol..
just get another one if ya know what i mean..lol.

Hope Ya'll are doin better than all the crap that keeps going down around here...
i guess it was my turn..
 

Tyger13us

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THE KVAN 4x4 MAN

Seen your post in my thread..
so you have some t-350 cases?
what would one of those cost..
im the poorest person you know.
thats why i was considering a bolt in case saver..
Or just use the best of all my parts and put it back together... the way it is...
And it did have the anti clunk spring installed in the case when i tore it down..
It was a bitch getting the center support out of it because of the spring..
i think who ever rebuilt the trans before me just used this case "as is" and said good enough for who its for...
seems no one wants to do **** right anymore,,
fix it and get it out of the shop and "we will worry about it if it comes back" seems to be the way it is anymore..
the trans came with the truck when i bought it.. and he said it was rebuilt....

So, when i did a ground up build of the truck,, 20k in parts, the only thing i didnt touch was the trans...
and after 8k miles,, its the only thing thats broke,, lol,, go figure..
 

HotRodPC

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Install one of these with a case saver. I just did one in a buddies 77 Corvette that looked like that, so far so good.
Yep, go this route for the win. If it's a bit more complicated or expensive than you really want to spend, then 2nd option is the case savers that have been suggested. They also work but not near as strong. With either option you can also do away with the anti clunk spring.
 

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THE KVAN 4x4 MAN

Seen your post in my thread..
so you have some t-350 cases?
what would one of those cost..
im the poorest person you know.
thats why i was considering a bolt in case saver..
Or just use the best of all my parts and put it back together... the way it is...
And it did have the anti clunk spring installed in the case when i tore it down..
It was a bitch getting the center support out of it because of the spring..
i think who ever rebuilt the trans before me just used this case "as is" and said good enough for who its for...
seems no one wants to do **** right anymore,,
fix it and get it out of the shop and "we will worry about it if it comes back" seems to be the way it is anymore..
the trans came with the truck when i bought it.. and he said it was rebuilt....

So, when i did a ground up build of the truck,, 20k in parts, the only thing i didnt touch was the trans...
and after 8k miles,, its the only thing thats broke,, lol,, go figure..
NO big deal and nothing to be pist about. You could be pist if you built it and then it failed but being you went with it as was, you can't be mad. If funds are an issue, just go with the case savers and you'll be good to go. They do work. Now if you're running 500hp or something like that, then I'd consider the bolt in and I'd consider that even if it were a good case. Those bolt in rings do add some strength similar to the Th400 center support that has a bolt that holds it in place.
 

Tyger13us

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Hey Dude! Larry! long time no talk/see......Thanks for the link....

i wasnt to sure if it would be ok to use those kind of case savers....
ive searched the internet till im blue in the face and it would seem that anything i found was saying they were junk and to get the full size bolt in one..

As every one knows what a bitch it is to R&R a trans in a 4x4 by your self on the ground in the middle of a field so to speak..
didnt want to do it again and or it to break and leave me stranded some place cause something broke,,, again....

i have been over and over reading your old build thread refreshing my memory......
i havent built a trans in over 20 years at least,, they never break down....hehe....

And since your here? what would cause the clutches in the Direct drum to go away,, as i said,, that and the band was all i found wrong.. everything else looks new...

2.. how far can i put the wide bushing down in to the direct drum?
i was thinking of seting it all on the pump to see when it would hit the rings and leave just a wee bit of space between them...
was gonna do it without the pump bushing modded up so id be sure to have enough room so the bushing wouldnt hit anything..
 

HotRodPC

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I've never had issues with the case savers not working. Now I have opened up cases where they had fallen but that may have been improper install, I dunno for certain. The best fix of course is the bolt in center support but there's a huge cost difference. I wouldn't be afraid of the case savers and I'd be able to sleep at night just fine. You can also use the anti clunk spring with those if you want for an added measure but it's not required. I've yet to see a case that broke all the way through on the those case lugs, so if I was in your situation, I'd just go with the case savers for the cheap remedy.

Direct clutches get used alot so it's possible they simply wore out. If they just burnt up in a short period of time, there was a bleed somewhere or a stuck valve leaving the dirct drum applied when it shouldn't have been. Same with the band if the servo was correct.

As far as that bushing, I'd try to just match up the markings where the old one was and leave it at that. Withouj having one here to look at I wouldn't swear to anything, but for sure you don't want it to where it can damage anything else or ride in the wrong place or cause you end shaft play to be out of tolerance which is a big clue that something will be rubbing or binding on something else.
 

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