2008 Pontiac Grand Prix won't go into any gears but runs just fine?

does it smell burnt? you might need a rebuild.

It sounds like something is ratteling when I put it in Drive or in Reverse?!?! But it moves now but with no power?!?! Something is giving out but I don't know what it is??

No Burnt smell that I could smell from it.

you need a newonverter and/or transmission

drain the tranny fluid & see how much metal & clutch material is in the pan & on the magnet.

I haven't had the transmission changed since I've got it because its been running fine and the fluid ain't never low but it is dark. Would changing the flluid and the filter help it out?!?!

you can try that , it seems like the torque converter is shot , you can change he fuild & filter it could help but it could also make it worst & not move at all. either way when you get the pan off see how much material is in it & the metal grindings on the magnet. how long have you owned this car? how many miles on it ? this sounds a little premature for a 4 yr old tranny unless it was abused or just excessive milage. no drive train warranty?

I'm just now hittin 100 on my miles. It will go in Drive and reverse now but there is no power. I won't have to replace my trans will I?!?!

your best bet is to take it to a shop and see what they have to say about it.

oh man... i think i know your problem and you will not be happy. those particular trannies... i think it's the L460E...have 2 input clutches. if you have a lead foot and stomp on it from a dead stop alot you run the risk of burning them up, quickly. that cause loads of other issues and you should take it to a tranny specialist and have him rebuild it. look up the different applications of the tranny, and you will find they made it with several different sets of ratios. the low gears if i remember correct you want to source from an alero, while 3 and 4 you want the ones from the bonneville. if you chip the car and can adjust the computers shift points your car should run like a dream for a long time, and top out around 140.

Would it help to change the transmission fluid and filter?!?!

tryt it what have you got to loose.