Rear diff lock activates by itself (1 Viewer)

[Raymond Samaha]

Hi Folks,
Coming back from Mexico, the rear diff started engaging randomly. Pretty strange when you're going 60 mph.
The central diff. does not come on. Just the rear.
I had to stop at the shoulder and turn the center diff and rear and front buttons on then back off and it went away.
Did it a couple more times after I crossed the border.
Local shop cannot find the problem.
Any ideas?
Thanks

 

[rc51kid]

Is it just the icon or are you sure it is actually locking the rear diff?

To check if it is locked jack up one rear wheel and put transfer in neutral. The lifted wheel should turn if the diff is open. Not turn if the diff is locked. If it spins you will also see the rear drive shaft turn which is why the transfer needs to be in neutral.

Make sure to chalk the wheels. It will role easily.

My dash icon was coming on 6 months ago.
I cleaned the plugs to the rear actuater and used dielectric green on it. Fixed the problem. But my lockers were not actually locking.

I think if you pull tue locker fuse when they are unlocked it should keep them from locking...I think

 

[Raymond Samaha]

Pretty sure it activated as the steering became more difficult. Actually the first time it happened, the light did not come on but the steering became very heavy and the car wanted to veer right pretty strongly.
Then it went away. I thought maybe I hit a rock in the road or something.

 

[NLXTACY]

Pretty sure your truck is telling you it wants to go back

 

[bloc]

Either bad locker switch in the dash, wiring to the diff lock computer near the blower fan, or said diff lock computer. I'm leaning toward diff lock computer since it shouldn't be engaging the rear without the CDL engaged.

Or maybe the clock spring is wonky and pulling it back into engagement?