Just replaced rear diff and still have noise

[sjorda1]

I have a 2002 Explorer and when I bought the truck last year the previous owner stated he replaced the hub bearings. I can not verify the bearings were replaced for certain. There is a roaring sound coming from the rear end that sounds like I have super swampers on the back. I deducted I had a bad rear diff. I purchased a rebuilt limited slip 3.55 rear diff off ebay from automotive parts unlimited.

There used to be a poster here that advertised their rear diffs. Anyway, I installed the rear diff and the noise is the same; much to my chagrin. When I am driving, I hear the sound at all speeds, regardless if I have my foot on the gas or not. When I turn the wheel to the right, the noise stops, when I turn the wheel to the left, the noise persists. I assume what I really have is a bad hub bearing.

Based on my symptoms, which side is the noise coming from? I assume when I turn the wheel to the right it shifts the weight of the vehicle to the left, which causes the noise to subside. Conversely, when I turn the wheel to the left, it shifts the weight to the right to the suspected bad side, which will not cause the noise to subside. In other words, I suspect I have a bad right rear hub bearing. What do you guys think? I just spent $900 on a rear end and the problem is still occurring. I am a little pissed off and do not want to do anymore needless repairs. Thanks for any tips.

 

[shooterdude199]

U joints?

 

[akdoggie]

You got it right. It definitely sounds like a wheel bearing. When you load the bearing the sound still stays the same, and when you relieve the bearing the noise is lessened. Time for a new right side bearing.

You can go between two buildings with windows down and hear the noise usually. I use an alleyway behind a hotel to listen to sounds coming from the rear areas. It works fairly well. lol

 

[Jaxjoradam]

If you drive serpentine down the street you will here the noise come and go...Then it's the wheel bearing. You always replace them in pairs. Failure to replace them can ruin your transmission...

 

[imp]

Check Wheel Bearings

Place jack stands under all 4 wheels under suspension, as close to the tire as possible. Or, remove the wheels (better yet, more work), run up a couple of lug nuts against the rotors snugly, have someone gently run the speed up to about 30 or so in drive, while you listen carefully at all 4 hubs- you can carefully use a long screwdriver as a "stethoscope", placing the blade near the hub on the suspension, and the handle end tightly against your little ear-flap thingy. If 4X4, not AWD, press "4X4 HI". AWD will turn 'em all automatically.

If your noise is really loud, you may not need the screwdriver. Still, placing it under the pinion area of the differential can prove out presence or lack of pinion bearing noise. This work must be done CAREFULLY and with CAUTION, but is not beyond the ability of most fairly mechanical persons. Be careful around rotating parts! I proved-out a bad rear wheel bearing this way, which none of us could positively isolate while driving in the vehicle, 2004 Explorer, not even as to front or rear! imp

 

[JCR]

Where are you and what are you doing with the rear you removed? Is it also a limited slip 3.55?

 

[vinceautopart]

We at Automotive Parts Unlimited are still selling complete 8.8 and parts for the Explorers. I don't know what happened to the advertisement but you can go to our website automotivepartsunlimited.com or call 800-270-5224 and ask for Vince

 

[Kevin-Truro,NS]

If you drive serpentine down the street you will here the noise come and go...Then it's the wheel bearing. You always replace them in pairs. Failure to replace them can ruin your transmission...

Who taught you that load of crap? Wheel bearings have no effect on transmissions.

 

[HCCA 250]

Who taught you that load of crap? Wheel bearings have no effect on transmissions.

Ditto...And,you need not replace wheel bearings in "pairs". A wheel bearing is good, or it is not. And, they can go at any time. Which means, you can get 100K out of tem, or 10K. Or, anywhere in between. Just because you replace them, at the same time dowsn't mean they will stay good for the same length of time. And, they are a PITA to R & R. One at a time costs enough!

 

[vinceautopart]

hub noise

sounds like it may be the hub bearing. yes, you're correct usually it is the opposite side of the turn because you are putting the weight on that side. so if you turn right and you have the noise then it will usually be the left bearing. also when you put the truck in the air and spin the wheels you should be able to hear something or feel some kind of resistance.

 

[tmaher]

i replaced one passenger rear bearing because the noise was unbearable. 737 engine whine comes to mind... Noise reduced 80%. it was such a PITA that i have not done the driver side. Took the shop 2 hours to get the old bearing out. Had to torch it. The side to side driving definitely pinpoints the offending bearing. I can live with it the way it is. uhhhhh. my wife can live with it the way it is. LOL. gonna buy her a new car this fall anyway.