tsoleno

I have a suspicion that my rear axle is developing a problem. I've noticed just a subtle noise when reversing , like when backing into a driveway over the last week or so. It is just starting and might do it once in 20 times. My first thought was it was a u joint, seemed like a creaking noise. Today I put it up in the air and the noise was more pronounced when it would do it. It is more of a looseness , clunky type noise. When the wheels are rolling, the noise happens and the axle shafts jerk. Going down the road, it couldn't be any smoother. Anyone have this happen? Keyboard opinions of what this sounds like?
There is about 130 K on the van now. It runs loaded where ever it goes. 2008, 8600 GVW 2500 . The axle lube was done at 100 K. I did a quick look into replacement rear axles. One has under 100 K on it , the rest seem to have at least the mileage I've got plus some. Think that it is a fluke or is that the usable life on these?

mountainmanjoe

post a video of it

Gumby22

Did you support the van by the frame or the axle when you lifted it? If by the frame, the axle is hanging by the suspension and will sway/move quite a bit with the wheels turning, so I wouldn’t worry too much about axle movement if it’s not supporting any weight.

My first suspicion is the parking brake shoes/hardware being worn - the linings are glued on instead of riveted and tend to fall off, especially if they’re the factory shoes. They usually make noise in reverse when this happens.

Even if the shoes have been changed, the cables and levers are known to stick and drag, so it could be the shoes aren’t fully released and are dragging slightly in reverse. Check the levers where the cables attach on each side - if fully released, the lever should be pointing away from the cable bracket. If one or both sides is stuck, use a hammer and punch to drive it back to the fully released position.

tsoleno

I appreciate your thoughts Gumby22 (Killer user name , mine has rear disc and I basically nutted the rotors down when I ran it - supported at the axle. No binding at the brakes at all. Calipers float freely. Today I couldn't make it make the noise. When it is in the air, it is like the differential locks up at will. I'll take a video when I get back to it. Thanks for the suggestion. For now, the noise goes away when I turn the radio up.....

Gumby22

I’m referring to the parking/emergency brake, not the service brakes. The parking brake utilizes the space inside the brake rotor hub (known as a drum-in-hat design).

The rear diff is limited slip - the reason it appears to lock up at will is because uneven drag on the wheels/hubs will cause it to lock up. With the wheels off the ground, uneven drag could be caused by dragging brakes or an axle shaft bearing that’s wearing out and causing drag.

tsoleno

One way to find out. I'll pull the rotors and give it whirl. Thanks,

SteveROntario

They cheaped out on the heavy rear axles at some point. Does yours have full floaters or a regular rear axle? The regular rear axles in a heavy duty application tend to have rear wheel bearing failures that junk the axle shafts.

tsoleno

I'm hoping that you were right on with your thoughts Gumby. Today I ran it up again with the rotors pulled and it didn't miss a beat. No abnormal anything. So I blew out the park brake shoes ect, Sprayed a touch of silicone Kroil at the pivot points and loosened the shoe adjuster up a tad. No leak at the seals. So back together and fingers crossed. I'll update should anything change. Thank you!

Uptownsport

If you put near any vehicle on the hoist and rotate a drive axle back and forth you get a noise like there is a bucket of gears loose inside the diff hsg.
People who are unfamiliar with this are always alarmed.

In short, It sounds like what you're describing is normal.

The little squeak or 'clunk' could be anything- Anyone who drove Mopars 60's- mid 80's knows the 'clunk' when engaging the transmission- they had numerous TSBs, but it was just the nature of the beast.

Differentials/Axles generally last the life of a vehicle- Excessive wheel spin on a one wheel wonder can (and will) seize the diff pinion gears to the diff pin. The pin will exit the diff hsg and rear axle will come to an abrupt stop.
But it will give ZERO warning (no noise) before doing so.

My opinion aside, there needs to be a specific reason for condemning a specific component before you replace something, axle or otherwise.

Here, it is just a noise.

tsoleno

Earlier in the week I turned around on a lawn and the wheel was spinning and it clunked / clattered which to me seems to be the locker trying to do its thing. I can't make the van make any other noises now unless the wheels have the opportunity to spin. Today I checked the fluid level and noted like an 1/8 inch of fine metal (magnetic) paste on the plug. Off the cover came an in a clean pan no other debris. I don't recall this 30,000 miles ago when I changed the fluid- Lucas. Took some pics, and reinstalled the cover. I didn't see anything disturbing other than noted dullness on the ring gear where it meshes w/ the pinion. I'm far from a qualified axle mechanic. I just wanted to see what I could see and get the GM lube in it. here's some pics some might find interesting. Any thoughts would be appreciated.