MY 2002 buick regal has started thumping into gears after about 15min of driving. I dont drive for more than 15min most of the time but when i do its annoying lol. IS there an additive I can use to fix this or will i need to replace my tranny?

Welcome to AF.

It would help to post your mileage on transaxle issues. Does this feel more like a harsh upshift? If so, a common problem is the PCS (pressure control) solenoid causing abnormal line pressure.

Get it scanned with a trans capable scanner/scan tool and see if a P1811 (max adapt, long shift) DTC is stored.

Sorry this was my first post, My car has 98,000 miles on it and yes it is harsh upshifts. Thankyou very much for your respones. this is a great forum im glad i found it. Ill get the car scan and see what comes up. I will post the results thanks again. :)

Thanks for participating and you are welcome. Also, review this thread which covers a lot of info on the issue(s). Good luck!

Click here (http://www.automotiveforums.com/vbulletin/showthread.php?t=899929)