help putting tranny back together

[DERBINATOR]

I decided to try rebuilding my TH350 and I got it all apart fine. Now I'm having trouble getting the parts to slide back together because of the new seals. Is there a trick to this? I cleaned it up and put atf on all the parts but they just don't want to go. Can I use white lithium grease or something along that line?

 

[dyeager535]

Being VERY careful, I used my feeler gauge set to gently work around the seals. Have to use a flexible blade, but one that isn't too thin. Too much force or too much flex, and it will cut the seal. Some ATF on the seal as you have done won't hurt to help move the feeler gauge blade around, but vaseline is a good one too. Fine for holding check balls and other pieces in place.

Basically just push the seal "down" in one spot, once the feeler gets the seal "seated" in that one spot, work one way or the other from that point...don't use a sawing motion or you will likely cut the seal. Just pull the feeler out, and press down right where the seal goes from "seated" to "unseated".

 

[DERBINATOR]

I used your feeler gauge idea and I found some tanny assembly lube and she went together. Got to put the pump and valvebody on tonight and hopefully get it back into the truck. I'm a little nervous beings this is the fisrt time for a transmission rebuild.

 

[dyeager535]

If it doesn't work right, you'll be that much faster pulling it, disassembling it, reassembling, and putting it back in.

I got a bit of practice on my first rebuild, hopefully you don't.

 

[Ryan B.]

Zipties also work good to compress lip seals when installing them.
yah, a th350 is kinda hard to put back together.. you must get all the clutches and drums lined up.. when you get it all back together and put on the front oil pump...if the input shaft doesn't spin and have a tiny bit of endplay.. its not put back together correct..
I did this my first time rebuilding a th350.. almost started tightening down the front pump some more until i realized the front shaft didn't spin.. i thought i needed a thinner front thrust washer to adjust endplay... but then i realized i didn't have one of the drums seated all the way down and splined with the clutches.
count the clutches... like if theres 5, you should hear and feel the drum drop down 5 times, and it will make a more metal to metal sound when it gets to the bottom and is fully engaged.

Good luck.

 

[DERBINATOR]

Got the pump put back in and endplay seems right and it does spin so everythings seems good. The one thing that did concern me a bit is the book I am using showed a primer valve and spring in the pump and I did not see one in my pump. Hopefully I didn't miss it somewhere. Also is it normal not to use all the parts that come in the rebuild kits?

 

[dyeager535]

What did you use as a rebuild manual?

The ATSG manuals I've used show pretty much every possible variation of the tranny in question, so if you buy a "kit" of parts, typically it will have more clutches, or steels, etc.

I'd guess that something like a TH350C would use a couple more seals or something than a standard TH350, so there might be an additional source of "leftover" parts.

The important question is, whats left over?

 

[DERBINATOR]

I used all the clutches and the seals that go in the clutch assemblies. There was a few o-rings, acouple of the brass or bronze bushings left over and seal that I'm guessing would go in the tail housing of a 2 wheel drive tanny.

 

[DERBINATOR]

Well its 2 in the morning . I put 7 quarts of atf in and it started coming out of the vent so I figured I better start her up and get the fluid pumping. I put it in gear and nothing! Maybe I need more atf? Added 2 more Quarts started it up and still nothing. Know I'm getting bummed when I see the transfercase lever!!!! Its still in neutral. Pulled the lever into gear and the tranny is working. I'll take it out for the maiden voyage in the daylight but I think I won my first trannny rebuild!!

 

[R72K5]

hell yeah!

how ws dealing with the snap rings and all that inside the trans ?

any special tools ?

let us know how its going

i dont know if i will ever attempt a tranny rebuild or not, im just unsure,, i can rebuild about anything else, but just not sure about trannies, hmm..

i tihnk it takes a special kind of person to do them,.

im an engine and chassis and suspension kind of person than anything else, by far,...

good luck

 

[DERBINATOR]

Took it for a short drive ,about 10 miles, and everything went great. Once we got pass the seal problem it went smoothly. I did improvise the slide hammers using threaded rod and a couple pieces of wood, and for a spring compresser we used the same treaded rod and a some steel welded into a U-shape and a flat piece. Worked great. It took me several months to get the guts up to do it. But now I'm glad I did. Saved bunches of $$$$! Hopefully it holds together long term.