i had a a th400 built by a race trans shop for my car. i had a leak and tried to make it home the last couple miles after it started slipping. found the leak and fixed it but now the car wont go in second or third. its a manual/auto shift and is all new, only got a couple runs on it and maybe a couple hundred miles since they rebuilt it. so i was wondering what things i could check, or if i need to replace the clutches, can i just get clutches and put them in. those guys that did the trans are good but expensive and i cant afford to have them build it again right now, hoped i could do something myself.

 

Sounds like its going to have to come apart..

 

i figured that but ive never opened up a auto before, was wondering if i could just get a clutch rebuild kit or do i have to get one of the whole kits with everything. and i saw most dont come with the bands what do those do and do i need to replace those as well?

 

This kit comes with the bands as well as plates, gaskets etc...You'll have to purchase a new filter separate though...

http://www.summitracing.com/parts/bmm-21041/overview/

It's not hard to rebuild if you've got an area to do it and a few tools. Snap ring pliers are a must. Here's a breakdown of the trans.

http://www.bulkpart.com/Merchant2/gr...f/3L80-400.pdf

I've rebuilt two so far. the first one got me in the 11's. I'll let you know how the second one does here later. Haven't had a chance to go to the track yet, but it shifts fine so far.

I used a 5 gallon bucket and a piece of plywood with a hole in the center resting on top of it as a stand. Remove the tail housing, put the output shaft in the hole and let it stand there while you disassemble.. Make sure the hole is large enough to allow the fluid to run into the bucket.

 

Won't shift or slipping after it shifts? Ck the vacuum line to the modulater. if ok pull the cover off the governor and pull it out and ck the gears.

 

thanks for the tips, you used that kit to get to 11's? i wasnt going to mess with the valve body because i like how it is now.

 

1st and reverse are fine but if i go to 2nd or 3rd it revs up for a second or two then starts moving slow like in a manual if you held the clutch half way down, or the clutch was worn out

pretty sure it has something to do with lack of fluid it completely covered the bottom of my car