Vehicle: 1990 E350 460V8 27'motorhome, 73000 miles. Rear drum brakes had new wheel cylinders installed around 57000 miles. Shoes were OK, maybe half worn.

Problem: Last month I was on a trip. Realized rear brakes were not working. Parking brake not working either (even after adjusting 1.5 inches on cable). Took to truck repair facility and the guy adjusted the star wheels. Working fine then, but about 2000 miles later (mostly highway) they were not working again.

Yesterday I tried to adjust them, but when I turn the star wheel on the one side it just springs back. Tried pushing the adjuster plate that holds it out of the way and was able to make a few increments of the wheel without it backing off, but it was very difficult. Had a stiff wire (about 3/32" dia) and could not get at the adjuster plate. Slot in wheel backing plate too small. Fi

Next, there is a lot of greasy black deposits on the wheel and backing plate from about the adjuster slot on down. Got to thinking maybe there is a leak. Since cylinders were done figured axle seals must be going. Can't tell by smelling the stuff or at least did not have the pungent rear end dope smell. Rear end dope within about 1/4" of filler hole.

Should I try adjusting with the special tool instead of screw driver? Maybe the screwdriver does not give enough of a turn to get one tooth past the adjuster plate.

But then why does it not self adjust? Because the motorhome only backs up very slowly?

Thinking of taking in (have to anyway for other work) and have the brakes gone over especially to see why adjusters not working automatically.

Thanks

 

I would guess that considering the loss of braking power, and the deposits you see, that it could be the wheel cylinders leaking. Take the drums off and see if you can see where the leak is coming from. I'm sure others will be able to give some advice about your situation.

Good luck!

 

Sounds like they didn't get the brakes set up properly when they were repaired. Drum brakes are real simple but they are too complex for some of todays mechanics.

 

Thanks for the input. I was going to wait until I got it fixed, but haven't gotten it into the shop yet (mechanic at the motorhome dealer is incarcerated, not sure when he gets out--drinking and driving--can't believe the owner told me that). Anyway. If the shop finds anything interesting I will post the result.

 

The main problem was that the rear axle seals were leaking. That is why I gave up trying to adjust the brakes and took it in. I had noticed the grease at the bottom of the backing plate area. Anyway, it appears the fronts wore hard with so many miles of no back brakes. Total job:

Front: new rotors, heavy duty pads, new calipers

Rear: new pads, seals, and hardware. Drums good but approaching limit.

Cost: likely around $1000 parts and labor.

Expectation: Not to have to do anyting to the brakes again for a long, long time.

Expensive, but not a rip off. This is a reputible shop that I have worked with before. And they are honest. Just that these big trucks parts are expensive.