My '97 Vanden has an irritating hum in the rear of the car. It's at its loudest at about 50-65mph. Once I get to 70mph, it is less pronounced. It is rotational and not related to the engine. I can shift into neutral and even cut the engine off and it is still humming.

Anyone have any guesses as to what it could be? I checked the differential oil and it's full.

Stumped.

 

https://www.jaguarclassicparts.com/u...ponents-normal

There is a TSB on how to remove the # 16 collar . Not having done it myself you can do it yourself and save some money . Don't go cheap on the bearing .

Could also be the wheel bearing .

https://www.jaguarclassicparts.com/u...-assembly-rear

 

The diffs fitted to the sedans from 1988 to 1997 have a problem with the pinion bearings failing.

I have replaced the pinion bearings for dozens of sedans and replaced diff units with reman units when I worked at the Jaguar dealer.

It is just the 'nature-of-the-beast'.

Just make sure it is the pinion bearing before you start throwing parts at the noise.

The output shaft bearings are the easiest to replace.

bob

 

Hi wilsongsx,

Just some random thoughts that may or may not be helpful in diagnosing the rear end noise:

1. In my experience, when the pinion bearing is failing a common noise is a whine like a jet engine, typically when lifting the accelerator pedal to coast. The sound seems to come from the transmission tunnel and center of the rear seat.

2. Differential output shaft bearings may make more of a howling or grinding sound, but you may not be able to detect which side the sound is coming from. If you see oil leaking from around one of the output shafts, that's a frequent indication that the bearing on that side is failing, and replacing the seal requires removing the collar and bearing anyway.

3. Rear wheel bearings may make a roaring sound that changes when cornering, and it is usually easier to identify which side of the car the sound is coming from than with diff bearings.

4. When the large rubber subframe bushes fail, they allow metal-to-metal contact between the subframe and body, conducting differential gear noise directly into the passenger cabin. This sounds just as you would expect differential gears to sound, and the noise increases with road speed but doesn't change much between acceleration and coasting but may change while cornering.

It is not uncommon to have more than one of these components failing at the same time.

I have had good success locating rear end noises by securely chocking the front wheels fore and aft, raising both sides of the rear end and supporting them on jack stands, starting the engine and with the brake pedal depressed, carefully putting the transmission in Drive and slowly releasing the brake pedal. Once I'm certain the car is stable, I carefully get out, lay alongside the car (never under it), and carefully probe with an inexpensive mechanic's stethoscope, touching the differential housing near the pinion bearing, each output shaft, and the rear hubs near the wheel bearings, taking great care not to touch any rotating parts. Obviously, this is safer with the car on a lift.

If you determine the source of the noise, I have lots of photos showing the processes of replacing the rear wheel bearings, the diff output shaft bearings, and the diff pinion bearings (rebuilding the diff). The photos are of our '93 XJ40 but aside from the lower control arms the components are essentially the same and the bearings are all the same part numbers. The large images aren't currently working, but my thumbnails and descriptions are viewable. See the photo albums at the link in my signature.

Cheers,

Don