Shifting Problems Grand Prix 2001

I have a 2001 Grand Prix GTP Supercharge Special Edition 3800 4 speet auto transmission.
When I accelerate and let the trans. shift,the car is sluggish and slow to go. If I manual shift it,I can accelarate better yet not correct.The fluid is full and is clean. Can anyone help? Thank you.

Sounds like my '01 GTP at around 43K miles. Ended up with a trans replacement when it got worse and worse. Though, it's been a long time and I don't remember the details of the symptoms.

I have a 2001 Grand Prix GTP Supercharge Special Edition 3800 4 speet auto transmission.
When I accelerate and let the trans. shift,the car is sluggish and slow to go. If I manual shift it,I can accelarate better yet not correct.The fluid is full and is clean. Can anyone help? Thank you.

i would still change fluid and tranny filter then take a magnet see how many shavings to got in old tranny fluid and if you find chunks time for tranny hope not.

good luck..........

Sounds almost like a cat converter issue. How many miles are on your car?

See this post regarding cat converter warrenty on your car.

http://www.automotiveforums.com/vbulletin/showthread.php?t=681283

I will give it a try and with hope I do not have to put my other trans. in. Thank you for you advise and time.