rebuilding a th400

[Jonny-K5]

how hard is it? i've never pulled a tranny apart before but i've done pretty much everything else on a car. i've got one out of a 70's pickup i'd like to swap in my old chevy thats got a slipping 400. it worked fine when it was in the truck, but i'll be putting in a stage 2 shift kit and higher stall converter(22-2500).

should i just install it and hope it doesnt burn up, or try tearing it apart and possibly screwing it up.

 

[mrk5]

My father-in-law and I rebuilt mine about 3 years ago. It wasn't terrible, but I'm glad there was someone else to help me. As I remember there were a couple of things that would have been very hard for one person to do.

It was acting funny in reverse the last time I drove it. After driving 20miles, I was parking in reverse and I had to rev the motor to 1200rpm to get it to move. I wasn't slipping, but just not engaging without running the Rs up.

So it cost me $100 for the rebuild kit, and I have 20,000 miles and 3 years on it. If it fails tomorrow, I figure I got my money out of it.

 

[dyeager535]

I don't think there is a better tranny to learn on, at least not GM anyways.

Buy a rebuild book (ATSG is popular but bad pictures) or a video, and have at it.

If JUST doing a shift kit and a converter, that is very easy, especially with the trans out.

 

[wasted wages]

There are plenty of great books and videos on rebuilding the T-400,,
The best way to learn is to dive in and just do it.
A digital camera or camcorder is also a good thing to have arround as you take the old one apart,,,your bench should have lots of room to lay the parts out as they come out of the case,,pay attention to the end play,,position of the thrust washers,the clutch packs as they come out of the case,,get a good kit with all the clutches and steels,seals and gaskets.
Most hand tools will do the job and only a few specialty tool are needed,,mainly a spring compressor and some lip seal tools,,but hey i've built many a trans and don't even own a spring compressor,,,I made one myself and it works fine.

B&M sells a kit that even has the instructions included,,I have built up many T-350's and T- 400's and a few 700r4's with no formal transmission training.
It's pretty much been roll up the sleeve's and dive in,,,,,experiance is the best teacher!!!! and if you run into trouble,,there is so much info out on the net
you can get out of most trouble by asking questions,,Hell,,you can even PM me if you get in a bind!!

 

[Jonny-K5]

thanks for the replies. i think im gonna just do the converter and shift kit and see how it holds up. its not my DD, just a play toy for messing around with.
if/when it starts to fail, then i'll try rebuilding it myself. gotta kill it first, thats the fun part anyway