Gmc m211 questions

[1944mb]

Greetings and welcome. Are both axles lockedup? I would start by jacking up one axle enough to get both sets of tires off the ground, then try and rotate by hand. If the wheels move a short distance, then stop, and you can reverse and do the same thing in the other direction its probably more drive train related. I'd pull the driveshafts cause they are best to move without driveshaft connected anyway. If the tires move freely it obviously drive train related. If they are froze solid you could try backing off the brakes. There are two adjusters per backing plate. 5/8" socket I believe. Rotate to the rear of the truck to back off. a turn should do it. Then see if they move. Let us know how it goes.

 

[hendersond]

Good advice 1944MB. The other think to consider is the parking brake. It is a band on the rear axle's driveshaft. The driveshaft is geared to the other rear axle's driveshaft. IF the parking brake is stuck, it may give the illusion both rears are locked up. The front would not necessarily "lockup" as there is a sprag clutch in the transfer case. The adjusters are cams as 1944MB pointed out. Turning them won't pull the shoes back if I remember right. It is possible the wheels are stuck, but less likely than most vehicles because of the design. There is no parking brake in the drum to freeze under tension. Also, the brakes are air over hydraulic not modern air brakes. Modern air brakes have the big spring that holds tension on the shoes to the drum. If all was in good condition there should have been no pressure holding the shoe to the drum. Also, the thing is a real bear to pull if not exactly straight ahead or to the rear. The rears bind hard as there is no differential between the axles. I'm interested to learn what you find when you jack up both sides of the rear axle and try to spin the tires.

 

[hendersond]

Sorry to Bonecrusher2002. We hijacked your thread. We should move this to a new one.