4x4 not engaging

[camohd]

I have a 2011 GMC 2500hd Duramax when I turn the knob to put it in 4x4 the shows that it should be in 4x4 but front wheels do not spin there is no noise to indicate that it is slipping in the transfer case thinking might be the actuator but not sure how to test that.

 

Thanks in advance

 

Sent from my SM-G960W using Tapatalk

 

 

[davester]

Put it in 4wd, chock the rear wheels and lift up one of the front wheels.

 

If you can't spin it, great, 4wd is engaged.

 

If you can spin it, look under the truck and see if the front driveshaft is spinning as you spin the wheel.  If the front driveshaft also spins, then most likely the chain in the transfercase is busted (but could be other things).

 

If you can spin the wheel, but the front driveshaft doesn't spin with it, and you can't rotate the front driveshaft by hand, then most likely, it's the actuator in the front diff not going in/out (for whatever reason, it may have failed, or there is a electrical problem).  If the actuator is working, then bits in the front diff are broken (the locking ring and the passenger side stub axle are common bits to fail).

[camohd]

Put it in 4wd, chock the rear wheels and lift up one of the front wheels.
 
If you can't spin it, great, 4wd is engaged.
 
If you can spin it, look under the truck and see if the front driveshaft is spinning as you spin the wheel.  If the front driveshaft also spins, then most likely the chain in the transfercase is busted (but could be other things).
 
If you can spin the wheel, but the front driveshaft doesn't spin with it, and you can't rotate the front driveshaft by hand, then most likely, it's the actuator in the front diff not going in/out (for whatever reason, it may have failed, or there is a electrical problem).  If the actuator is working, then bits in the front diff are broken (the locking ring and the passenger side stub axle are common bits to fail).

Thank I will try this

Sent from my SM-G960W using Tapatalk