Is it possible to disable the auto headlamp feature. If I turn it off auto its always back on the next time I start the truck. Thanks

 

There is an ambient light sensor on the dash that controls this as well as the DRL's.

There is a couple of mods for this. Multiple versions involve fiddling with the ambient light sensor on the middle front edge of the dash by the windsheild (you can find lots of info on this on the various GM truck forums). These involve adding resistors and/or cutting the wires and adding a switch and/or just disconnecting it. The other method involved modding the actual headlight switch. You can disassemble the switch, grind off a small ramped spot which is what makes the far left "off" position spring loaded and will allow it to remain in the actual off position. https://www.silveradosierra.com/elec...n-t649361.html

There is a catch though. Since it uses the same ambient light sensor for both auto-headlights and DRL just about anything you do to disable one also disables the other. So if you mod it to shut off the auto-headlights function your DRL's will also be off. In most of the US DRL's are not required by law though but in Canada they are.