Thread: 2007 Grand Prix trans has issues shifting

Good afternoon. I have a base model 2007 Grand Prix 231 that when i kinda-sorta want to get on it, the trans has a habit of trying to find the correct gear. And sometimes, hits said gear on the harsh side. After taking it's sweet time doing it.

I was a' wondering if anyone else has had or seen this problem, and if so, what the fix was. ECM reflash, etc. If i drive it normally, like an old man would, i have no issues.

Thank you.

No, it doesn't happen just at WOT. Usually anything at or over 1/2 throttle. And no tire chirping. It is almost as if the transmission is confused as to what gear it should be in.

So say i take off normally from a stop, and then punch it. The trans feels like it doesn't know what or which gear to grab. Along with wheather or not to unlock the torque converter.

I can get the tires to chirp at WOT from a standing start. But i rarely do that. I do not like buying tires............

I did a trans service 2 months ago, and this did not fix anything.