To give a little quick history, I bought my present 97 GS regal with a GM reman. trans that after 4 months of owning it starting slipping. First I noticed it only on hard starts (shuddering out of the hole on hard launches), then it started to slip when downshifting into passing gear while driving. So last year I replaced the trans. with a 2001 LS regal trans with 20k on it, did the HD swap and tuned the pcm accordingly for the 3.29's. I also replaced the converter with a stock replacement GM converter new for a 2001. As of last fall things were fine. Now that winters over, I've been tuning it getting ready for the track, and I went to practice my launches and the trans. shuddered just like it did with the original trans. (almost feels like wheel hope, but it's definitely the trans). So I scanned some and I was able to duplicate the issue.
So I tried something different by launching the car while I was in 1st using the shifter, instead of 3rd like normal. The problem disappeared. So right after I tried it in 2nd, 3rd and 4th and the issue was still their. I'm actually able to duplicate the problem power braking only slightly, basically tapping the gas real quick while holding the brake. No shuddering what so ever in 1st, but in any other gear from a dead stop it does it. Over all the trans. doesn't slip while driving, shift's perfect all the time and theirs no code at all. I'm kinda at a loss as to what this could even be....so any direction you guys can point me in to start ironing this issue out would be great
