Vehicle door locks activate lock and unlock while simultaneously downshifting the transmission, the engine dies, the dash cluster stops working, engine starts again, dash cluster begins working again. After this occurs, when the vehicle is shut off, there is a loud "pop" sound heard over the speakers and no interior lights. The vehicle may or may not have any cab power. Cycling the ignition provides little to no help. After the vehicle sits for a while, it may or may not start again. The vehicle stereo will randomly change from FM to aux. The a/c panel will flicker and the blower motor will fluctuate. This can also be seen while watching the battery gage on the instrument cluster. It will go from around 14 volts DC to around 9 volts DC and back up again.

- Alexander , AR, USA

I was traveling on a divided highway and approaching a slow moving truck in the right lane ahead of me. There was another truck behind me in my lane. I moved to the left lane to pass the slow truck. Just after I began the pass my pickup slowed quickly and began flashing error messages: Stability control disabled, engine power reduced & service stabilitrak. The truck behind me had moved up close and followed me around the slow moving truck. I was unable to accelerate and continued slowing quickly. I had just enough room to swerve in behind the slow truck as my speed fell below its speed. The truck behind me narrowly avoided a rear impact with my truck, which, I believe, would have been catastrophic. I pulled to the right and tried to speed up. About 40 mph was all my truck would do. I stopped and got out the manual. It said to reset the stabilitrak, turn the vehicle off for 30 seconds. I did that and the truck seemed to functioned normally, at least as far as engine power. I still had traction control & stabilitrak error messages and the service engine light was on. I was able to return 40 miles to my home town with no further incidents. I was able to get my truck into the Chevy dealer on the 30th. The service rep recognized my description immediately as a "throttle sensor" failure. It was repaired under warranty. There have been no further incidents. My concerns are dual: First, only luck and years of emergency vehicle operation training enabled me to avoid being hit from behind by the following truck when my truck unexpectedly and without warning lost power. An impact would have likely be life threatening considering the speed and proximity of two trucks. Second, subsequently, I have found multiple internet reports of this issue going back several model years and my service paper work indicates a GM service bulletin for it exists.

- Hobbs, NM, USA

This is a dealer demo vehicle, first 2235 miles were demo. During my first morning (12hours after picking up at dealer) of ownership I was descending down a hill with the cruise on, and the vehicle proceeded to over speed approximately 5-7mph. I travel this hill both ways to/from work daily and this happens everytime. I though this might be an abnormal adjustment within the computer/etc so while taking in to the dealer for a TPMS (tire pressure monitor system) issue I mentioned the overspeed issue to the service write up and they said that it was normal. I don't agree, but maybe it is. It does adjust back to normal cruise set speed but is unique. I had a 2002 Dodge Ram 1500 previously and it did not do this, and I have drove otr (over the road) semi-trucks and know the difference with overspeed being normal and abnormal. I would like this to be looked into, as it could be a hazard that could lead to unsafe situation.

- Tomah, WI, USA