Rear wheel or diff bearings??

[stevets]

2002 4x4 Sport Ed with ABS - The dreaded bad bearing whirr has come to roost. Its really hard to tell if it's the wheel bearings or the differential bearings.
The noise has gone from a "what is that new noise" kind of thing to almost intolerable in +/- 100 miles. I've had vehicles in the past that went many miles before the bearing noise got so much worse!
There is no oil leakage into brake/wheel area and the diff is full of newish gear lube.
Anybody had wheel bearing go so fast? Do the diff bearings fail??

 

[the great him]

tell us when this sound is occurring...? like do you hear it going around corners / left or right? do you hear it under accleration, deceleration, crusing, coasting...? what you gotta give more info other than i hear a noise that is a "whirr" noise.

 

[meRockboost]

Jack up rear end and grab the tire at 9 & 3 and wiggle it. Any more than slight is bad.

 

[ShooterMcGavin]

2002 4x4 Sport Ed with ABS - The dreaded bad bearing whirr has come to roost. Its really hard to tell if it's the wheel bearings or the differential bearings.
The noise has gone from a "what is that new noise" kind of thing to almost intolerable in +/- 100 miles. I've had vehicles in the past that went many miles before the bearing noise got so much worse!
There is no oil leakage into brake/wheel area and the diff is full of newish gear lube.
Anybody had wheel bearing go so fast? Do the diff bearings fail??

Regarding the bolded part, the best way to check for that is to remove the ABS sensor to look between the seal and the bearing. That area will soak with gear oil long before the oil makes its way into the rear drum brake.

 

[stevets]

Ive tried the 9 and 3 wiggle test and there is no play. The sound is constant and is completely dependent upon ground speed. It does not change in tone or frequency when cornering, in neutral or even coasting with the engine off. It changes with acceleration and deceleration only to the extent that the speed of the vehicle changes - no louder or softer.
At first i thought that the transfer case was engaged but the front shaft spins free.

I did note that when I had the wheels off the ground, there was a bit of slop in the forward/backward rolling of the tire. That is - the wheel moved some distance before the axle engaged.

 

[stevets]

Thanks for the tip Shooter. Ill check that. But I am surprised at how quickly this came on! One would expect to hear a little something as this got progressively worse but it was like,,,BAM!

 

[the great him]

well by your statements it does not sound like either bad wheel bearings or bad pinion bearing. it sounds more like tires, and road noise, like maybe alignment is off or tire pressure is off and wearing the tires funny, or even differing road surfaces. a wheel bearing will get louder under cornering, say like the left bearings will get louder going around a right hand corner as you load the outside of the vehicle with transient weight shift. a pinion bearing will be loud under a load, say like accelleration or deceleration say like you are cursing along and get off the gas a little and you can hear and feel it load up and make the noise. it could be a carrier bearings as those really dont have a load affect on them as much as the other two... but your gear oil would be dark and discolored from the heat if that was the case. try flushing out your rear diff and seeing what that does for you. maybe put in some thicker gear oil if you want and see what that does for the sound.

 

[stevets]

Update: this was the pinion bearing. Still unclear as to why this went bad and deteriorated so fast. The only speculation I can get is that the "slinger" that splashes oil on the pinion and carrier bearings was somehow defective or pooched up. New pinion and carrier bearings plus seals, gaskets, etc installed = $1800.00......Ouch!

 

[the great him]

Update: this was the pinion bearing. Still unclear as to why this went bad and deteriorated so fast. The only speculation I can get is that the "slinger" that splashes oil on the pinion and carrier bearings was somehow defective or pooched up. New pinion and carrier bearings plus seals, gaskets, etc installed = $1800.00......Ouch!

wow you got ripped off... you coulda had a ARB locker installed with compressor for that

 

[stevets]

Now you tell me!