Rear hub/ rear end problem

C

Cotterski

New member
One of our club members recently had new brake drums installed by a reputable Model A garage. When he got the car back, it made a terrible noise (grinding/banging). When we jacked up the rear end, we were able to move both hubs in and out at least 1/8 inch. We have done numerous diagnostic tests, but it logically is related to the brake job. The drums do not hit the backing plate, but the mechanic installed shims on the shaft of the axil.
We ran the car on blocks, and the noise was present in all forward gears, but not in reverse. Does anybody have any good ideas?
Rod
 
Did it also get new brake shoes?
I'd ask the guy that worked on it what all was done and what was replaced.
Removing and replacing drums and shoes should not change the axle end play.
 
Even if the shop did a full brake job, shoes tracks drums etc, the axle play would have been there before the job was started unless the rear end was pulled and gone thru at the same time.
Was a full brake job done or just replace the drums?
Did the parking brake shoes get switched left or right? Were the drums turned? Where the shoes arced to drums? Even if it was just the drums replaced the shoes would still need to be arced to new drums.
 
The best person to ask about the problem is the mechanic. Obviously he has done something improperly. The problem is his with no further expense to the owner. Wayne
 
The brake job was complete, drums, shoes, etc., with shoes arched to the drums. The symtoms of the problem didn't exist before the brakes were done. Opinions of club members include; transmission bushings, U-joint, and differential. All of these issues should have been apparent before the brake job, and would normally get worse gradually. The symptoms appeared immediately after the brake job was completed. Could something have been damaged during the drum/hub removal?
 
I wonder if the proper tool was used to pull the drums off the tapered axle shafts. If not, it could be possible for something to have been damaged in the rear end if enough force was exerted...

Just a wild thought.
 
Maybe they did a few hole shots after working on the car....
Does your club feel 1/8th end play is to much and that's what's causing the noise?
 
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I agree with redmodelt in post #4. the play in and out would have been there before the brake job. That play is controlled by the wear at the beveled gear, inward with the mesh of the teeth with the differential spider gears and out wards with the flat backside of the beveled axle gear mating with the flat surface on the inside of the carrier. If the carrier bearings are worn to the extent that they allow some sideways movement of the carrier and the ring gear (no preload) it can make the end play worse. If the seal at the axle housing allows grease from the axle bearing or lube from the diff to coat the end of the axle housing bearing stub and rubs on the inside of the hub without much scraping noise. Wiping of the grease during a brake job might be able to cause some noise. Then adding shims to the axle would move the hub out to eliminate the limiting factor of end play that the hub provided and give the full extent of end play. The fact that there is a change in the noise in reverse adds credibility the possibility of bad carrier bearings. Remove the shims and see what you get. Model A is known for being able provide usable service even though wear has exceeded all limits but you may be at the tipping point.
 
I agree with post #4 redmodelT... if there is in and out play on the axle/hub it was there before. If there is the noise as stated I would look for things like the inside hub studs/hub rubbing on the e-brake pins... it is possible it could be catching in rotation. Look for witness marks of rubbing..... if so the hub/drum/axle shaft need to be addressed. If you have an issue and had a schooled "A" mechanic on it I would revisit with them for the issue. It's certainly not fair to knock them without knowing and understanding the issue. Most cars have issues many don't even know about... and so the list never ends. This may be one on yours....

I thorough inspection and diagnosis is in order by someone who understands rear ends and brakes on them.

Larry Shepard
 
Also note that the cotter pins for the emergency brake toggle lever and links go to the inside, not the easier to get to outside. It is possible that if the cotters are to the outside on the e-brake assembly, the cotters or pins may be dragging the inside of the hub and lugs as there isn't much clearance there and with excess axle end play, the situation gets worse for an interference! Open the brakes up and inspect! There will be telltale signs of interference.
 
Coterski, please, after you get the drums off, come back to post what you find. Every can learn from this thread if it continues on to the final solution.
 
Like Vince, I was also thinking the parking brake might be the problem. Are the retaining springs in the OUTER most holes on the two brackets? If not then they can catch on the brake carrier.
 

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