Hi, this is my first post here. I am here out of desperation, please read
my story carefully and shoot any questions or suggestions to me that you
might have, as silly as they might seem. This gets long, so hang with me
I have a 1996 Impala SS. Last year, my 4L60-E transmission was giving me issues. The 1-2 shift seemed forced, the trans. not shifting immediately, instead bouncing off the redline before slamming into gear. Shortly after, my 3/4 clutch burnt up and I lost 3rd & 4th gear, forcing me to rebuild or upgrade.
I chose to upgrade with a TeampTripp (www.teamtripp.com) Performance 4L60-E transmission rated for 600 horses. I did not ever send him my core, so the transmission that he sent me was completely different from my original. At the time of professional installation, I had a new factory torque converter installed, as a requirement of my warranty. Now, with less than 1,000 miles on this transmission, I am experiencing some of the same troubles as before, as well as a few extras:
-The 1-2 shift is hesitant, again bouncing off the redline before a shift is made in most cases. However, some of the times it shifts perfectly.
-The 2-3 shift is slow, taking a moment in neutral while my rpms climb the tach before shifting into 3rd.
-When cruising at 50-60mph, the transmission has trouble selecting a gear, switching back and forth between 3rd and 4th. A burning smell (the clutch?) arrives in my nostrils.
-Coming out of a slow corner (turning out of a parking lot) and applying 3/4 throttle, there is a loud grinding noise from the rear, the car revs, and the gear is selected after several seconds.
-When cruising at 30-40mph in top gear, and I demand for WOT, it revs again in neutral and selects a gear after about 1 second.
I have tried contacting the owner of TeamTripp but he has not returned phone calls or emails yet, and this needs to be taken care of soon as this car is my daily driver (and only car). At the advice of some members of the NAISSO Forum (National Association of Impala SS Owners www.naisso.net) I replaced my throttle positioning sensor (TPS) with another factory unit from AutoZone.
As reference points, although I've been assured that this is not the cause, I have different than stock tires, stock being 255/50 17, mine being 285/40 17. I was informed that a computer reprogram was not necessary as the sidewall difference is not significant enough (.5") to alter shiftpoints. I was also informed that the shift is determined by engine speed rather than road speed (RPMs instead of MPHs) and sidewall height will not affect RPMs, obviously.
Other than that, my car is basically stock, excluding visual and audio enhancements. No performance modifications, save a cat-back exhaust.
I'm becoming desperate here, and I cannot afford to replace my transmission again. Any advice or direction in this matter is greatly appreciated.
I have now been told it might be an ECU problem. Also, my posi just burnt out.