4 wheel drive problem - 2001 Yukon

[tancooker0]

Have a problem with my Yukon. Thought I would see if anyone has an idea on where to start.

 

It's not going into 4 wheel drive. It's the electric push button type. I can push the 4-hi, 4-lo, 4-auto, and for each of them the light by the button will flash for a few seconds, but then the 2-wheel drive button will light back up. I had the actuator on the front diff out, and when I get someone to hit the 4-wheel drive button the actuator extends out for the few seconds it's flashing but then it goes right back in when it stops flashing. I can hear the actuator on the transfer case going when the buttons pushed, but didn't have it off to see if there was any movement. Anyone have any ideas? Should I still take off the transfer case actuator to see it there's movement, or is it if there's noise it's working?

[efritz]

do you get a service 4x4 light?

[00Silverado4x4]

I'd pull the transfer case motor to see if it moves. The noise is not enough to tell you it's working or not.

[tancooker0]

do you get a service 4x4 light?

Nope, no service light.

[tancooker0]

I'd pull the transfer case motor to see if it moves. The noise is not enough to tell you it's working or not.

 

Ya, I figured I'd have to try that this weekend. Didn't have time to do it last night before dark.

[efritz]

It sounds like an encoder motor issue but they are expensive, so best to get an accurate diagnosis with an appropriate scan tool