Hi Guys. This is my first post. I have a 04 with 58000 miles on it. About 2 days ago it started what seemed to me was a misfire betwen 1300 and 1600 RPM"s. I carried it to the dealer. They keep it 2 days and finally called me and said it wasn't missing fireing, but they needed to flush the transmission. I won't get it back until next Monday. I don't know if that will fix it or not. Has anyone had this problem? In 5th gear under a load it would make the car shake. You could go past 2000rpm and it would smooth out. Griff

I got my car back from the Dealer today. They fixed the problem. It was NOT missfireing as I though. They flushed the trans. and installed a 242106 BG Trans kit. Can anyone tell me what this part# is? Griff

I got my car back from the Dealer today. They fixed the problem. It was NOT missfireing as I though. They flushed the trans. and installed a 242106 BG Trans kit. Can anyone tell me what this part# is? Griff

Sorry I cannot answer your questions but your service tech should answer each and every question you have. Im curious about it as well....although I have no trans issues I am not a fan of the crappy shifting these things do and am having a rather famous tuner work out mine through a computer retune once I install my 3:42 differential. Does yours seem to be shifting way better now?

I really never had a problem shifting, just the vibration between 1300 &1600 rpms It shifts perfect now.

I've searched the forums and I guess I have the first hard tranny failure of a Base model XLR.

It happened while doing some "SPIRITED DRIVING" at NCH last month.

Symptoms: When auto or manual shifting from 2nd to 3rd gear, the tranny shifts out of 2nd but won't shift into 3rd unless I let off the gas pedal. If I don't let off the gas pedal, the engine over-revs as though I missed 3rd gear in a manual transmission.
There is no problem shifting from 1st to 2nd, 3rd to 4th, 4th to 5th or even down shifting from 5th to 4th for passing.
I drove it from BG, Ky. to my daughter's in Wisconsin and then to Colorado Springs, Co. where I had it checked out at Red Noland Cadillac. They informed me that they would have to replace the tranny and I would have to leave the car there.
I could not do that so I drove it home and am in the process of replacing the tranny myself.
I was lucky getting the replacement tranny from gmpartsdirect.com as they had them on sale.
Here is an interesting fact about this tranny!( P/N; 96042733, aka 5L50-E)
This is the same tranny used in quite a lot of the GM vehicles, i.e. Pontiac, Olds, Buick etc. In other words, it IS NOT a special tranny for the base model XLR!

Now, I have a question for jjmoody.

Did you change your differential gear rational from 2.93 to the 3.42 as you were going to and how is that working out?
At 75 mph in high gear, how many rpms is your engine turning over and what effect did it have on your highway mpg?