Tranny got rebuilt, but I still have problems!?

[94 SHO OFF]

I just got my 1994 ATX tranny rebuilt with a bigger tranny cooler and the trans go shift kit. When im doing my mostly city driving the car shifts a little hard into second when im not on the throttle. For example When I give it gas just before it shifts into 2nd ill let go so it can shift automatically and it will give a thump. The tranny was rebuilt about a week ago and did this the moment I got it back. My 1-2 shift is very strong at higger RPM's but at normal launches it doesnt feel as quick, I rebuilt the tranny due to my 1-2 shift being very hard with slippage. If anyone can help me Id greatly appreciate it.

 

[HopefulSHO]

Have you tried keeping a constant (even if light) throttle for the 1-2 shift? Changing your throttle position like that right before a shift dosent give the tranny time to change pressures completely. Something like that

 

[94 SHO OFF]

ive tried that, the 1-2 shift under a light foot still feels a little unsmooth, its not as strong as if you give it alot of gas.

 

[Mr Anonymous]

Go back to the shop that rebuilt the tranny.

 

[Axianator]

ive tried that, the 1-2 shift under a light foot still feels a little unsmooth, its not as strong as if you give it alot of gas.

A weak 1-2 shift while under light throttle is very possible (and likely) with the newer revised TransGo kits, especially if one is still running under the factory program.

Out of curiosity, how many miles have you put on the rebuild thus far?

 

[94 SHO OFF]

I did the rebuild about a week ago so maybe 170 miles.

 

[Axianator]

I did the rebuild about a week ago so maybe 170 miles.

IMO, I'd (gently) drive the car for a couple hundred more miles and see if the problem persists. If the low-throttle shifting you described is unsettling or persists after that time, then I would definitely do as Chris suggested and pay your tranny shop a visit.

I assume you're still running with the factory (D4U1) computer and no aftermarket chip?

 

[94 SHO OFF]

Yeah, I don't have any other chips in the car, im just running the stock set-up. Would you suggest a chip or would that make the problem more persistant?

 

[Axianator]

Yeah, I don't have any other chips in the car, im just running the stock set-up. Would you suggest a chip or would that make the problem more persistant?

Assuming the "problem" is caused by what I described, then yep - a properly-programmed chip should be able to correct the slow/weak shifting at low-throttle. If it were me, though, I'd give the tranny a few hundred more miles of gentle break-in before I did anything.

As for the tranny banging into gear when you let off the throttle, the only real solution at present for that is to try and avoid it.