At start up if I have my foot on the brake pedel at all I get a Service Brake System message. If I turn the truck off don't touch the pedel all is fine. I assume this has to do with lack of pessure at start up. Does anyone else have this problem?:help:

I get that too. Sometimes happens even if I have my foot nowhere near the break pedal. I took it to the dealer and was told it's a know bug in the ABS firmware. As of a couple months ago there was still no fix.

The best story I've heard is that it's because the ABS computer gets the idea the front wheels are turning because of the vibrations during startup.

I took mine to the dealer just before my 3/36 ran out and they said they didn't have a fix. But latly it happens alot and when at the dealer they said they won't even look at it with out a charge because I'm out of the 3/36.

I would call GM assistance and explain your experience with the dealership. They will fixt it free if you call. I had a warranty problem, the 100.00 deductible, and the gm people put me on hold why the called the dealership, and they took care of it right there on the phone. Good luck.