One side axle brakes catching fire

Sure, immediately after adjustment. Brakes apply with different pressure at each position. Similar pressure, but one wheel end will always apply a little harder than the others.

 

Was it a trailer? And was it right rear?

 

Could be a number of things. Blown wheel seal mixed with a long brake application, brake stuck on etc.

This sort of thing is EXACTLY the reason to climb under the truck and take a very close look at stuff every few days. If you're relying on a shop to look the truck over once every couple months you're only setting yourself up to fail.

 

Air leaks in a system usually tend to affect the brake furthest from the valve. What position waa the s cam in? I think @wore out mentioned the brakes camming over. Very possible.

I've seen s cam bushings so neglected that the brake chamber springs can't pull the slack adjuster back in.

A broken spring on the brakes could allow the bottom shoe to contact the drum at all times.

 

Awesome explanation. Props, for taking the time to explain all of that to everyone. This is why I have always hung out in shops at my employers, asking questions. I want to learn all I can, so I can help myself, when out on the road.

 

Seized slack adjuster as in the pin of the clevis was rusted tight?

Most common failure of a slack adjuster is it’s inability to make adjustments, otherwise…?

One of the most common causes I’ve experienced, is the camshaft bushings going without grease. Eventually they are wore clean out, or…. they are so dry the brake chamber doesn’t have enough pull to rotate the camshaft back to the released position. Therefore the brake shoes drag on the drum creating heat.

Years ago I made a run to Massachusetts in the 77 Freightliner conventional. It had just came out of the shop from service and brake work (new brake chambers).

It was drizzling the rain that day, not hard just enough to keep the wipers on low, intermittent would have been good.

Pulled in to a toll booth and here came some toll booth worker with a fire extinguisher…. he was hollering my wheel was on fire!

Long story short, the shop guy apparently forgot to tighten the nuts on 1 of the maxi’s and the bottom nut was completely gone. Brake shoes were not releasing as they should, and kept a constant drag on the drum, don’t take much to create a lot of heat over many miles. Wasn’t even enough to notice while driving.

Lot of things can create the same problem….

 

If you have to pull the pawl out to turn it backwards or loosen the shoe yes it should be. Those are the least likely to not hold and back themselves off when getting on the brakes. They do need greased to self adjust properly.


You can hold the pawl out and turn the adjustment back and forth after a few shots of grease then repeat a few times may help them. I would try that before replacing.

 

Seized adjusters leave loose brakes. Not tight brakes.

Your hub and bearings could have seized up.

 

Being that I pre-date Auto Slack Adjusters; I seem to 'distantly' remember that one of the initial brands of self adjusters had a special prodedure for manual adjusting. I recall, back then when almost EVERY driver was capable of manually adjusting brakes, all sorts of published warnings to NOT adjust the new auto slacks UNLESS you were trained. Shortly after the brake certification for tecnichians started and drivers couldn't adjust unless they had the same certification training.

All these years later is there any prohibiting issues for manual adjusting a loose slack?