Whirring noise in rear

[ryanr623]

There is a whirring noise coming from the rear of my car. It can be heard from the time you start moving, through highway speeds. It has been happening for a year or two, but has gotten worse lately (not too bad though). It seems worse at lower speeds. When i brake and am slowing to 5 mph or so it sounds the worst. This may be because no engine noise, but it seems worse then.

I can hear it when i stick my head out the window. I initially thought wheel bearing because of this, but i have heard this gen 4runner is notorious for pinion bearings going out. Is this true? Can someone provide a pic of the pinion flange so i can check for play?

Is there any way to tell if its a wheel bearing or pinion bearing without jacking the car up?

 

[ryanr623]

Anyone?

 

[Nelsonmd]

Anyone?

Jeez, give it more than 45 minutes...

The pinion flange is the flange that the rear drive shaft bolts to. Just jack the rear wheels off the ground, disconnect the drive shaft, and spin the flange by hand back and forth. You should be able to feel if there is any play.

My experience is that wheel bearings get louder at high speed, not low speed. Not sure about pinion bearings.

 

[ryanr623]

Jeez, give it more than 45 minutes...

The pinion flange is the flange that the rear drive shaft bolts to. Just jack the rear wheels off the ground, disconnect the drive shaft, and spin the flange by hand back and forth. You should be able to feel if there is any play.

My experience is that wheel bearings get louder at high speed, not low speed. Not sure about pinion bearings.

Great. What is the average cost to replace a pinion bearing?

 

[Nelsonmd]

Great. What is the average cost to replace a pinion bearing?

I don't know. The bearing itself is about $40, plus there are a bunch of one-time-use parts in there that you might want to replace. The procedure is in the factory service manual. Search for the documentation and reference thread to get the FSM.

If you mean by taking it to a dealer, then I really don't know.

 

[cordrayj1]

when my front pinion bearing went thats exactly what it sounded like and did. from the time you begin to move it makes a whine. sounds like you have some pitted bearings due to bad fluid or time.