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Could someone describe what it sounds like when wheel bearings fail? I am trying to track down a new noise in the rear of the truck....I am pretty certain it is in the rear. It sounds like a dull grinding or dragging noise. I initially thought a brake shoe had dislodged in the drum, but I have determined that is not it. I still want to back the rear shoes off completely and see if the noise goes away. I read in one of the Pinz manuals that the springs could be bad allowing the shoes to drag, so this should isolate that.

I also drained the rear diff and wheel drives fearing metal particles or low oil, but that was fine too. If not bearings, my next thought is the e-brake. The brake works and releases, but could it be dragging causing the noise? I did forget it was engaged and drove in 4x4 low for a stint.

With the rear of the truck in the air, wheels and drums off, truck in neutral (T-case too), there is gear noise when turning the rear wheels by hand. I cannot remember if this is normal or not??

Thanks for your help guys!

Wheel bearings often make some noise when driving straight down the highway, but it changes pitch or volume as you go through a corner. Brake noise is less variable with cornering, but should change some if the brakes are engaged.

You could drop the fluid from the wheel drives and check for metal or changed color. Pull the brake drums and clean everything out and visually inspect them for broken or bent parts, then readjust them and try it.

Gear noise when off the ground is kind of normal, but seems to vary from truck to truck. There are multiple gears being driven in the differential. If you lock that differential, then you're driving the main drive shaft including the parking brake. Does the noise occur when you're moving things like this? Does either wheel move if you wiggle it up and down?

The ebrake typically grabs pretty tight. If it's working, it'd be hard to drive even in low range. Maybe try stopping on a hill, engine off, and disengage/engage the ebrake and listen to it. It might help to have a helper drive while you listen out the back of the truck.

undysworld wrote:Wheel bearings often make some noise when driving straight down the highway, but it changes pitch or volume as you go through a corner. Brake noise is less variable with cornering, but should change some if the brakes are engaged.

The noise seemed constant, but at speed was drowned out by all the other Pinz noises. The truck seemed to run fine at 95KPH.

undysworld wrote:You could drop the fluid from the wheel drives and check for metal or changed color. Pull the brake drums and clean everything out and visually inspect them for broken or bent parts, then readjust them and try it.

No metal, but the colour has me thinking. What would a change in colour indicate? Heat increases?

undysworld wrote:Gear noise when off the ground is kind of normal, but seems to vary from truck to truck. There are multiple gears being driven in the differential. If you lock that differential, then you're driving the main drive shaft including the parking brake. Does the noise occur when you're moving things like this? Does either wheel move if you wiggle it up and down?

The sound is there whether all diffs are locked, or not. Comes from just rolling the truck. It became apparent to me while on the trail because of the slow speed and less noise, but was not there before my 3 hour drive to the event. TechMOGogy heard it too while in the back of the truck. I haven't tested the bearing for movement yet, but I will do that tonight.

undysworld wrote:The ebrake typically grabs pretty tight. If it's working, it'd be hard to drive even in low range. Maybe try stopping on a hill, engine off, and disengage/engage the ebrake and listen to it. It might help to have a helper drive while you listen out the back of the truck.

The e-brake still seems to hold, but I was able to move the truck in low. Kicking myself for that, as I always check. What damage could I do from driving like that? Glazed disks? Could they be dragging?

Thx Paul!

Pcolette had gray fluid apparently caused by a broken lock plate on the axle shaft which allowed the two bolts which secure the gear onto the end to back out. The color seemed to be caused by wear on the inside of the brake backing plate, and preceded one bolt actually going through the plate.

My ebrake once make a rattling noise, most noticeable off-road. I disassembled and cleaned it, but found no obvious issues, reassembled it and haven't noticed it anymore. Not sure what to suggest might be causing your noise.

Well, I dumped all the remaining fluids and nothing obvious. The DS drum was hard to remove and hard to reinstall, so I backed off the shoes a little, just to see if that helps. I will take it out for a test tomorrow....rolling down driveway should be enough...and if I still hear it, I will drop the cone.

Thx for the help Undy, I do appreciate it.

Stay tuned...


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Maybe a stethoscope would help locate the source. If it's consistently making noise, it might be detectible on jack stands. Taking off that cone was no fun, in my case, and you'd hate to do it just for grins.

FWIW, I'm glad to offer what I can. The only guarantee I can give about my advice is that it's worth what you paid for it!

Good luck with it.

I have taken off the cone to examine the disks for the hand brake. If you don't have to remove it, I would avoid doing so. It is a pain in the rear.
I had to lift the body to get the cone off and it was not a lot of fun putting it back together. In the process I discovered that my disks were fine and
a little clean up was all that was required.

If you discover that your disks are shot, I ordered a set that I am willing to sell at the price I paid.

Hope it works out for you.

Thanks guys.

I am going to hold off on the e-brake removal. I do not think that is it. I will see if the noise is still there tonight.

On a positive....but more costly note...with all the crawling around under the truck, I found a cracked boot in the rear that will need to be replaced.

Took the truck out for a spin and whatever the noise was seemed to be gone or much quieter. Then, I backed into my garage and it reappeared. Shifting into reverse is fine, but it just seems the dragging is more prevalent in reverse....then reappears when going forward again.....head scratcher for sure.

I haven't inspected the front brakes yet, as the sound seems to come from behind me....but who knows.

Maybe loose part/s in the brake mechanisms? If the noise is coming from the wheel drive/s and is evident only in reverse, I'd suspect the brakes.

I assume you cleaned and inspected everything, looking for damage, if you had the drums off already. (If not, )

The DS drum was hard to remove and hard to reinstall, so I backed off the shoes a little, just to see if that helps.

Why was this hard to remove/reinstall?

Sometimes this is caused by the brakes adjusted too tight, or probably more commonly by a ridge around the inner surface caused by wear from the shoes and rust where the pads do not contact. Even if the shoes are adjusted right, this ridge can cause problems getting past the shoes.

How are you adjusting the shoes? There's the way the manual specifies, and then there are lots of other ways. Remember that the fronts have two adjusters on each wheel. Remember to bolt the drum on tightly while you adjust the shoes. Set 'em up correctly, according to specs, and then see how things work.

undysworld wrote:Maybe loose part/s in the brake mechanisms? If the noise is coming from the wheel drive/s and is evident only in reverse, I'd suspect the brakes.

I assume you cleaned and inspected everything, looking for damage, if you had the drums off already. (If not, )

Yes, but only the rear....as I assume it is coming from there. I was getting to the front but I got called away by the Wife.....

undysworld wrote:Sometimes this is caused by the brakes adjusted too tight, or probably more commonly by a ridge around the inner surface caused by wear from the shoes and rust where the pads do not contact. Even if the shoes are adjusted right, this ridge can cause problems getting past the shoes.

Ya, I think I over adjusted the last time, making it difficult to get off, so I backed it off.

undysworld wrote:How are you adjusting the shoes? There's the way the manual specifies, and then there are lots of other ways. Remember that the fronts have two adjusters on each wheel. Remember to bolt the drum on tightly while you adjust the shoes. Set 'em up correctly, according to specs, and then see how things work.

I have always followed the manual and I use three lugs on the drum before doing so...may have adjusted more the last time.

I think I over adjusted the last time, making it difficult to get off, so I backed it off.

Shouldn't be a lot of variance. Tighten the adjuster until the drum locks, then back off 2 clicks, or maybe 3, IIRC. Tighter, and things will drag. Looser, and you'll have excessive pedal travel.

Assuming the noise is from a wheel drive, if it were me, I'd start by re-cleaning, re-inspecting those rear brakes for anything funky. A broken spring, shoe clip, evidence of weird movement of parts, strange wear on the shoes etc. Then I'd clean up any lip on the drums. Then I'd reassemble and properly adjust the shoes. Then I'd go for a drive.

If it's still noisy, I'd get someone to drive for me so I could hang over the rear end and try to better pinpoint the location of the mystery noise.



Anybody else got any ideas? Come on. You can't tell me I'm the friggin' brake expert around here!!

Well, I took the front wheels off tonight and found nothing loose or broken, but I did make note of something....the shoes were very tight to the backing plate....meaning the small tension springs must be working well. When I pulled on the rear shoes, I found that they would come away from the back plate fairly easy.

Could the little tension spring be worn enough to allow the shoes to move/shift in the drum when tightened, causing the dragging? How tight should the little spring be?

Thanks again for the help!



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I got occupied with a clutch replacement on my Ural, so didn't have time for the truck.

Today I decided to tear into the PS rear as this is where I think the noise is coming from. I took apart the shoes and removed the entire hub. This wasn't the daunting task I anticipated. I feared for the lose bolt, but it doesn't look like anything is loose in there. Do I have the newer setup Undy was referring too?
One thing I did notice and what I still think it may be, are the retainer springs. I bought four from SAV and did a comparison.

Can you guess which of the springs was on the rear most shoe on the passenger side?

New spring on the left, next pair from PS and last pair from DS.

My suspicion is that there was not enough tension allowing the shoe to move in the drum. Reversing seemed to aggravate it.
Does everything else look okay to you guys?



I noticed this on the back plate, but is outside of the sealed housing.




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Berger,
Purchase an inexpensive digital thermometer with a lazer sight (like from Harbour Freight here in the states). Its an invaluable tool as has been suggested in several boards. After driving, check the temp of each hub. If there is a big imbalance, the highest temp may be adjusted too tight or the very lowest one too loose. In addition,d checking the head temps or exhaust headers can identify which cylinder may not be producing.