I have been having problems with the "service 4wd" for the last 2 years, after cleaning connectors , I thought the problem may be over, every once and a while the service lite comes on, I reset it , test it , everything changes (lites), I hear it change to low 4wd, but today, it snowed , I changed it to 4wd auto, 4wd, and the lights came on, and then I realized that the front wheels did not respond and drive. I was slipping as it was in 2wd. Any suggestions ? Don
My 4WD button lites up but the front wheels are not engaged on 2005 Chevrolet Silverado 1500
by donandmax in Portland, OR on December 06, 2013
ANSWER by ProfessorG on December 06, 2013
Check and/or change the front lock actuator. The actuator at the front diff locks the front axle.