Rearend noise

[charlesvolare]

I've been doing a lot of work on my rearend. It's an 8.25, and I recently broke the spiders and tore the carrier up. New carrier w/bearings and a lunchbox locker to replace the spiders. Took everything apart, pinion out, seals replaced and cleaned it the best I could. Used an entire case of brakeclean and clean enough to eat out of. Put in 75w-140 (I believe, it was the heavy duty/towing recommendation) which is thicker than what I was running before.

Reassembled and set back up properly and I realized how worn out my suspension was. A few weeks later I had gathered everything up to replace the suspension- new shocks, shock plates, Calvert springs. The springs are super stiff and have aluminum bushings in the front, poly in the rear.

Soon after the new suspension I noticed a slight noise, kind of like a very lightly dragging disk brake or a slight wind noise, but it's barely noticeable over the exhaust and everything else. It starts at around 35-40mph and doesn't get louder or vary with speed. I've gotten new tires since and it's not the tires.

It seems to be from the rear passenger side, but from the driver's position it hard to pinpoint exactly. With the rear in the air and the car stationary, I can't seem to recreate the noise. No play in the axle. It hasn't gotten worse in the few weeks it's been doing it.

Could the aluminum bushings just be transferring more noise into the car than the old iso system with the rubber bushings? Wheel bearings weren't cleaned perfect and starting to go?

 

[Duke5A]

Wheel bearings will change their pitch with road speed. When my Dad put caltracs in his Diplomat the solid bushings transferred a fair amount of noise and made the ride a little bit harsher. Your noise could have been there all along.

 

[charlesvolare]

Wheel bearings will change their pitch with road speed. When my Dad put caltracs in his Diplomat the solid bushings transferred a fair amount of noise and made the ride a little bit harsher. Your noise could have been there all along.

That's what I was thinking with the whole not louder when faster deal. Any idea of what it could be? Or just not worry too much about it unless it starts to change?

 

[Aspen500]

In some cases you almost have to let it get worse (IF it gets worse) to find what's causing the noise. The solid bushings will transmit noise to the body big time. It's like driving a pickup with the sliding rear window open and hearing the whir of the rear axle.

It's rare BUT, just last week I had a vehicle (can't for the life of me remember what it was, they all blend together after a while, lol) that had a humming type noise starting around 20 mph and continue until 45 mph or so. Steady noise, no variation in pitch or volume no matter the speed or load. Turned out to be the right front wheel bearing. That was a you know what to narrow down!

 

[AJ/FormS]

If you have a yoke on the back with a big ol' dust shield on it, check if it's rubbing on the carrier. While you are under there check to see if the E-brake cable is rubbing on the driveshaft.