In the past someone mentioned to me that the transmissions last longer when the PERF SHIFT is enabled. At the time we were talking about my 99 regal GS but I'm sure many other 3800 platforms have this option. What are your thoughts on the validity of this??
Performance shift only changes how long each gear is held and I think depending on the application, it may even firm up the shifts too. Actually, I just looked at my *-10 file and shift pressure is altered between normal and performance.
I'm also under the impression that, the less time it takes for the trans to apply the bands, less slippage occurs which = less clutch/band wear.