[modern] Rear hub noise problem revisited

Tom, my noise was more of a moaning or hum that varied with road speed. It
also resonated in the car’s structure and got much louder at certain speeds.
The damage to my bearing race was composed of lots and lots of small pits.
If your bearings have a different sort of pitting, or if your damage is more
advanced than mine was, it’s easy for me to believe that it could cause a
grinding noise.

John Pring emailed me to tell me that he’d had two rear axle bearing
failures on other cars he’d owned. In both cases, he said, the problem came
from a failed seal that allowed dirt and water into the hub. My inner seal
had come loose from the hub and was spinning in its bore.

You can check this out with little disassembly. Take off the wheel, remove
the ABS sensor, and look down the hole where it came from. You should be
able to see enough to tell whether the seal is still doing its job. If the
seal is dislodged or if there’s grease everywhere, you probably should look
into it very soon.

If the bearings are very far gone, there’s an even easier test. Jack up the
wheel, grab it at front and back, and wiggle. If there’s any play at all,
the bearings are shot. These hubs use preloaded bearings to give zero
wobble. (My noisy bearings still had no detectable wobble.)

Bob----- Original Message -----
From: “Tom” clown@creativecarnage.com
To: “Bob McKeown” <@Bob_McKeown>
Sent: Tuesday, July 10, 2001 2:19 AM
Subject: Re: [modern] Noise problem solved!

| Would you describe the noise as a grinding noise? I hear a noise that i
| would describe as grinding coming from the rear right wheel of my 89 XJ40
on
| occasion. Like you said with the noise your JX6 made, mine was also
| insensitive to engine load.
|
| Thanks,
| Tom
|
| ----- Original Message -----
| From: “Bob McKeown” <@Bob_McKeown>
| To: modern@jag-lovers.org
| Sent: Saturday, July 07, 2001 12:26 PM
| Subject: [modern] Noise problem solved!
|
|
| > I posted several months ago about a persistent problem with my 88 XJ6.
| There
| > was a noise emanating from the rear that sounded like a combination of
| tire
| > and bearing noise. The noise was completely insensitive to engine load,
| > varying only with road speed.
| >
| > I had bought new Michelins a while back, but they made no difference in
| the
| > amount or character of the noise. I also replaced the axle stub shaft
| > bearings in the diff, which likewise had no effect.
| >
| > Yesterday I decided it was time to change the hub carrier bearings, and
| > bingo! The left side inner bearing was toast. For some reason the inner
| seal
| > had begun to spin in the carrier, ultimately allowing dirt into the
| > assembly. The bearing race looked like it had been in a very localized
| > hailstorm.
| >
| > Fifty feet into my test drive, I knew the problem was solved - I heard
| > nothing from the rear! All of what I had thought to be tire noise and
all
| of
| > the moaning and humming I attributed to bearings were gone. The silence
| was
| > eerie, since the noises had been there for the entire year I’ve owned
the
| > car.
| >
| > Now the car sounds as it should. At highway speed, the main sound is
from
| > wind over the A-pillars. My newly-upgraded stereo (thanks, Stefan)
sounds
| > like a million dollars.
| >
| > I never dreamed that a bearing could make so much noise yet exhibit no
| other
| > signs of failure - no excessive play, no overheating. Now that I know
what
| > an XJ6 really sounds like, I’ll be a far more critical listener in the
| > future.
| >
| > Bob McKeown
| > Nashville, TN
| >
| >
| >
|
|