I own a 06 Impala that had the same symptoms as you described, I am no grease monkey or anything, but if your ever owned a truck, it felt like when u-joints were worn when you went from reverse to drive. Some time my car would get to approx. 3000 rpms before engaging forward motion, from reverse.
I had the tranny flushed and the filter changed when I first noticed. Worked well for several hundred kilos, but it retured. I took it to a dealer, (no coverage over 168,000 klms). They noticed metal filings at the filter and proceeded to replace what I believe was the clutch plate(I'm somewhat ignorant on transmissions). They showed me a plate and ball bearings and where they show be on the plate. Wear marks were obvious where these bearings were supposed to sit on the plate. It convinced me that my problem was solved. No reoccurance since, runs great, with smooth gear changes. Done the trick for $1,700.00. Dealer labor costs killed me, but problem solved.
I am experiencing overheating problems with my car. Are you? If so, please advise.
Monday, October 19th, 2009 AT 7:45 PM