Transmission problem??

Hello all,

I have a 2008 GXP and am having an issue I've never had before with all of my previous cars. When I'm driving around 60-63 mph (cruise is not on) the rpm's are around 1900 or so and all of the sudden they drop about 300 and the car sort of stalls so to speak for a second or seems as though you lightly press on the brake and then it goes back to normal and will do this multiple times. If I had to guess what a transmission slipping felt like I'd think that was it but I'm not sure since I've never dealt with it before. Also when I shift into manual on the transmission I hear a high pitch whine noise from the engine compartment, not sure if that's related or not but thought that might help determine what's going on. I've got 57,000 miles on the car and I did just change a lower transmission cooler hose a week ago because it was leaking. When I did I noticed the little bit of fluid that came out had a shimmer to it so I changed the fluid and filter just to be safe. The original fluid was actually pretty red still. Any help would be greatly appreciated!

Thanks,
Tim

Did this happen before or after you changed the fluid? If it happened after I would make sure the filter did not pop off, and make sure the fluid is not over or under filled.

Was there any debris in the pan?

Check for tranny codes?

Did this happen before or after you changed the fluid? If it happened after I would make sure the filter did not pop off, and make sure the fluid is not over or under filled.

It did happen before but it seems like it's a little worse now but that could be because I'm paying closer attention to it and I've checked the fluid probably 5 times since the fluid change and did end up putting a little more in for the first few times I checked it but it didn't need much.

Was there any debris in the pan?

Check for tranny codes?

There wasn't really anything super scary in the pan. The magnet was pretty sludge covered and there was a little shimmer in the fluid when you shined light on it. You could see very small metal shavings/specks. How would one check for tranny codes?

With a code reader or a scan tool......just because your light is not on, does not mean there isn't a code in history....

With a code reader or a scan tool......just because your light is not on, does not mean there isn't a code in history....

I have just a simple code reader so I'll see about borrowing one and taking a look and let you know what I find.

With a code reader or a scan tool......just because your light is not on, does not mean there isn't a code in history....

No tranny codes were found......

It's possibly a TCC problem.....only way to know for sure, it to test drive with a scan tool attached, and watching transmission data as the problem occurs....

It's possibly a TCC problem.....only way to know for sure, it to test drive with a scan tool attached, and watching transmission data as the problem occurs....

Looks like I may just end up bringing it into a tranny shop. I'm really wondering what the heck the high pitch whine noise is when I put it into manual though. Every time I do put it in manual that noise starts and then it starts smoking by the radiator where one of the tranny cooler lines go. This car is giving me fits.....:screwy:

Update....

I ended up taking my car to a shop. $1709 later I have a new (refurb) torque converter in it. I called GM prior to all of this to see if they'd help out since I've read all over that these transmissions are dropping like flies and the guy I spoke to on the phone said he doesn't disagree that they've been having issues with these transmissions so he set up a service appointment at my local GM dealer to have it diagnosed. The diagnosis was a $3400 tranny replacement and GM said they wouldn't help (they basically made the dealership the scapegoat for that though. They told me the dealer said they wouldn't help so when I talked to the dealer they said since I didn't buy the car from them that the dealer couldn't help. Very unprofessional in my opinion how they play finger pointing games.) so I brought it to another place that actually took the time to see why the transmission was having issues and only replaced the converter and not the entire transmission. I'm not going to give up though with GM, in my mind it's ridiculous to expect a consumer to be ok with forking over almost $2,000 on a transmission that's not even 60,000 miles old. I've read on other forums and articles that people are on transmission number 3 so maybe I should consider myself lucky??:eek:

I wouldn't feel lucky if I had to put out $1700 on a car that has less than 60,000 miles.