Please help. 2005 gtp quit moving.

**burnt orange gtp** · 12-24-2019

So I could really use some help. I have worked in the automotive field my whole life but I'm not the slightest bit skilled in front wheel trannys. So, I'm driving my 2005 gp gtp(comp g) down the hwy at about 60 mphs. Car in front of me is driving slow. I pull out to pass, car downshifts and then acts like i threw it in neutral. No movement of wheels in drive, reverse or with paddle shifters. The car does have 300,000+ miles on it and has original trans. The trans has never acted out in the slightest bit. Not sure if any noise occured when problem first happened as I was jamming to radio, but i hear no strange noise while increasing rpms. Axle shafts seem to be okay. Im wondering if possibly a diff could cause these problems or if im looking more towards a complete rebuild. Any help or opinions would be greatly appreciated.

**Scottydoggs** · 12-24-2019

sounds like rebuild time. them comp g trannys are not interchangeable either. it needs to be the same unit from a comp g to use a used one too.

if you hammered it hard to pass that guy the input shaft might have snapped.

**burnt orange gtp** · 12-24-2019

I have a friend convinced that it's a differential. Any chance that holds true? Any way I can check myself to find what damage may have been done?

**burnt orange gtp** · 12-24-2019

Didn't hammer any harder than any other day.

**Scottydoggs** · 12-24-2019

when a dif goes you feel it trying to catch. they not wear out as much as explode when the pin falls out, you hear a chipping sound first then the pin comes out far enough to blow the case up.

the tc could have blow up too, when mine went it would drag the idle down low, and make it pretty hard to start up. would go into gears but was more locked up vs free revving.

a busted input shaft makes it 100% in operable.

at 300k how did the fluid look? still red? if its all dark and burnt up its rebuild time for sure, thats a load of miles.

**burnt orange gtp** · 12-26-2019

Fluid still looks really good, smells fine. I am concerned the car isn't worth the rebuild. Motor still runs great. Did head gaskets 50,000 miles ago. Everything during the teardown was replaced or still looked great. cylinder walls looked great. The car has been an awesome car. But it is also a Michigan car and rust has crept in. I'm having a hard time justifying a trans rebuild on a rusty vehicle with 300,000 on the clock.

**Scottydoggs** · 12-26-2019

well either sell it needing a trans, or part it out. or the cost of a trany is surely less then another used car. just depends on how much you like this car still.

**Supercharged99** · 12-26-2019

Originally Posted by Scottydoggs

well either sell it needing a trans, or part it out. or the cost of a trany is surely less then another used car. just depends on how much you like this car still.

My thoughts, too, especially after all the work put into the engine not too long ago.

**burnt orange gtp** · 12-26-2019

Thanks for the responses guys. It was info I was hoping not to hear but it does support my first instinct of a rebuild.

**FordMan77** · 12-26-2019

car-part.com

find another '05 and grab the trans. Swap it in and enjoy for another 300K and not have to worry about getting someone else's car with unknown history. Or swap it in and sell it to get more $ for another ride.

**tomsteve** · 12-27-2019

i got the trans rebuilt on my 08 back in june. $1800. only 104k on the clock and very little rust so worth it to me. i dont think id do it with a 300k mile car,though

**burnt orange gtp** · 12-28-2019

Finding a comp g trans for it has proven to be an extremely tough task. I work for a gm dealership and have a lot of contacts and connections, not to mention the internet. From what I understand just being a 4t65e-hd with the 329 final drive gear isn't enough. I have yet to find any. not even a high mile trans. I have tried that car-part.com as well.