Trying to help my neighbor out here. They have a 01 GMC Sirerra recently purchased without owners manual and looking for help in engaining and disengaging the 4 wheel drive on the fly.

Any assistance would be appreciriated.

Thanks,
Chris

Im assuming your just asking for the directions on how to set it. Is it push button or does it have a shifter? doesn't really matter you either press the 4hi or put the shifter into 4hi and slow down to under 5 miles/hr. It should engage.

4lo is a little trickier only cuz you have to put the transmission into park before shifting into 4lo