I own a ‘99 Tahoe. 2-wheel drive / Police package. 317K miles.
As of late, when driving, the rear wheels will, all of a sudden, lock up bringing the truck to a screeching stop.
It occurs at various speeds, during both acceleration and deceleration. No brakes are being applied when it happens.
Two mechanics have looked at it checking the brake system, transmission, and rear differential.
Neither can identify a problem. Thoughts?
After it locks up, does it unlock? How did you get it back home?
Securely get your Tahoe (Z56?) off the ground with rear wheels & tires off as well. Take every safety precaution.
Safely secured, up in the air, 'drive' until the problem replicates itself.
Should be easier to inspect the rear axle immediately after the fault to find out if there's anything wrong with it.
Can't think of any 4L60E weirdness that would explain this behavior. My bet is something wrong with the rear axle.
At 317,000miles, you could simply try installing a different / younger one ...
(Was GM's original tire spec for your Tahoe PPV 235/70VR15? If not, what was it? Just curious to check ...)