One problem related to turn signal has been reported for the 2004 GMC Sierra 1500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 GMC Sierra 1500 based on all problems reported for the 2004 Sierra 1500.
When the weather is below freezing the turn signals do not work until the vehicle has warmed up for atleast 20 minutes. Also the speedometer does not work, and when it does start working it is never the correct reading. It will stick as high as 70 mph, and to bring it down I have to keep restarting and shutting off the engine.