Well guys I got my th350 tore down for rebuild. It was orginally a 4x4 trans, but im installing the long output shaft and tailshaft housing.

I just need to clean up the outside of the case somemore and I can start reassembly. I bought the TH350 street/strip kit from Dana a Probuilt.

I also have a Haynes manual plus I printed a write up from carcrafts website.

Anyone have any tips/tricks or suggestions before I start the assembly? What assembly lube should or shouldnt use? What about clearances on the clutch packs. What works the best?

The trans looks like its in good shape. I could have run it if I hadnt had to replace the tailshaft. The bushings look good. Should I replace the bushings or just use the one in the trans. The kit has new ones, but the one in the trans look almost new. The trans might have been gone through at one point. I dont know the full history of it.

Any advice would be appreciated before I start the build.

thanks.

 

Get it as clean as you possibly can. Cleanliness is the single most important thing you can do. I'd suggest taking it to the quarter car wash early in the morning on a warm sunny day, with a can of 4MA and a can of engine degreaser; and be prepared to stick the wand in EVERY SINGLE hole in the transmission. That's lots of holes.

I usually clean internal parts with diesel fuel and then lacquer thinner. It's important to get everything clean.

Dry all the parts with compressed air. Blow all the holes in the case out with air. Let it sit in the sun for a few hours to finish drying. Verify that it's clean.

Stack up the clutches for .030" - .045" of clearance. If they're too loose, it will shift solw; if they're too tight, they will burn up from rubbing together too much when they're not supposed to be engaged. Make sure everything is clean.

Use Trans Gel for assembly lube. Vaseline will also work. Make sure it's clean.

And I almost forgot to mention - the cleaner you can get everything, the better. You don't want a SPECK of dirt in it ANYWHERE.

Don't use towels to dry or wipe things, they can shed lint which can hang up valves or plug filters. Lint is not considered clean.

Oh, and make sure every part is as clean as you can get it.

 

What about the bushings? If they look ok, should I reuse them or replace them?

 

If they're OK, re-use them.

If you don't have bushing tools, you can't really change them out anyway, without doing more harm than good.

About the most fun you'll get to have, is getting the lip seals on the clutch pistons to go into the drums without damaging them (VERY important); and aligning the 2 halves of the front pump.

 

Yeah, I will have to go slow and easy with the lip seals. Maybe us a feeler gauge to help. There is a trick by putting the pump in the top of the case to line it up. I will try it and see how it works.

I am going to drop the case off a a trans shop and see if they will clean it in there washer. That should clean it up real good. Then I can take an air hose and blow all the holes out.

 

Most bushings in the TH350 will need to be replaced. You have to go by the clearance, and not how they look. As for the clutch clearance, forward .020" - .040", intermediate .030" - .040", direct .050" - .080", low/reverse .030" - .060".

 

Thanks Dana. I planned on calling you when I was ready to assemble. I will go ahead and replace the bushings.

Now you sent me a extra clutch for a shim that was cut to put under the intermediate piston. Right? Also was I suppose to get a HD spag with that kit? It listed it on the web site. I wasnt for sure.

Sorry for all the questions. This is the first full trans rebuild that I have done and just want to be sure on everything. I have enjoyed working on it so far.

thanks.

 

UPDATE!!

I got all the bushings replaced except the 3 small ones in the pump. I will take it by a trans shop and get them to replace them.

I set up the direct clutch and had 0.060 clearance with 4 clutches and steels. I have the direct clutch piston at the machine shop being turned down for the extra clutch and steel.

Any advice in getting the direct clutch piston seated with the new seals? Just mocking it up, I had to remove the old ones just to get it in.

Everything is going good, but slow.

 

UPDATE!!!!


I got the trans in and it seems to be doing great.

Thanks Dana for the parts!

And thanks to everyone for the advice. I really enjoyed the build.

Now to just get to the track and get some timeslips!!!