Which wheels spin when?

[wormwood1978]

I have an 08 4.2, 4wd.

I was chasing a wheel noise today and had all my wheels up. In 2wd, my driver's rear spins, in 4wd high and 4wd low, both fronts and driver rear spins. Between 2wd, 4 H and 4 L, my passenger rear doesn't spin. Is this normal?

 

[mrrsm]

This Video is an Excellent Generic Breakdown of this subject:

 

[Mooseman]

Check your glove box sticker for the code G80, which would indicate that you have the locking rear differential. There have been rare cases where the truck was a 4x4 but didn't have the G80. If you do have it, maybe the conditions aren't right spinning by itself in the air to activate it. Here's a video showing how to test it.

 

[wormwood1978]

Thank you for the response. I don't have a G80 according to the placard.

 

[Street]

Question, when you had it in 4wd, did the one rear wheel spin relativity double that of the fronts?

If so, either something on the wheel that is not spinning is dragging - wheel bearing, disc brake, or perhaps the parking brake. That dragging may well be the source of the noise you're tracking down.

if not, rear diff trouble? (would be rather unlikely, but not impossible)

 

[Mooseman]

If both fronts are spinning and only one rear, then it's normal for the one rear wheel to spin double speed of both front wheels. If only one of the fronts spin, then front and rear would spin at the same speed.