Hi everyone, I recently changed the battery in my car since it died on me and after i installed the new battery the transmission doesn't shift correctly. I figured it might have something to do with the alternator so I replaced that but the problem still persists. I did not have a single issue with the tranny before the battery switch but now if i take it easy going down the road when it shifts at 3000 rpm it stays there for a bit wanting to shift and 2-3 seconds later it shifts. Sorry this is really long I just wanted to give you guys a lot of info.

BTW my car is a 2001 Monte Carlo ls

 

Is your PCM tuned differently than factory??

My old '02 LS, my current '05 SS, and my bonneville have aftermarket tunes and everytime the battery gets unhooked I need to drive about 100 miles before my shifts feel normal.. I have no idea why this is but have you drove for that long yet? Might just need time to readjust..


Does anyone know why this happens?? I know what hes saying by the whole "2-3 seconds of hang time" between shifts.. Theyre just SOOO soft and take forever. I feel like I need to let off the throttle just from the feel of it.

 

Tune or not, all modern electronically-controlled transmissions "learn" the driving habits of their driver and change their shift points accordingly. It's not an instant process. 100 miles sounds about right.

 

Thats kinda comforting to hear...

 

No my pcm inst tuned differently from the factory. So the problem will probably go away after 100 miles once the trans "learns" the driving behavior then?

 

Another thing to remember is the Service of the Trans Fluid it's good to change that every 50K check it, it should be a red color. If it's brown it should be changed out.