MrGorsky

Well-Known Member
Full Member
Yesterday on the motorway I noticed a 1KHz ish whine from the back of the car.

It came in at 70mph, and you couldn't really hear it below that speed.

It was only there when cruising on steady throttle, as soon as a hill came, or I accelerated, or decelerated it went away.

What is the most likely cause. Should I start saving for a new rear diff?

I've just serviced the car and greased the propshaft UJs and checked the rear diff oil level, and it's all good.

I also swapped my wheels around, but it doesn't sound like tyre noise. Could that have an effect?

Car has done about 84,000 miles.

Many thanks in advance!

Al.
 
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Recently, I had a whine when I coasted and the consensus here was that it was the differential. I has already replaced the transmission filter and fluid, rotated the tires, and replaced the brake pads. I checked the fluids in the torque converter and both differentials. All had fluids that looked like swamp goo. I began with the rear differential and although it looked ok, it did have a slight resistance as I turned it by hand. The whine was still there. I then replaced the front differential. My old differential had a loose center nut on the flange that allowed it to wobble. Before I put everything back together, I noticed that the hub/wheel bearing had a slight grinding noise as I turned it by hand. I replaced it as well. To satis my curiosity, I took the old hub to a shop today to have them punch out the wheel bearing. When I handed it to the Mechanic, he immediately said, "It's toast" when he turned it. The moral of the story is that you may also check your hub/wheel bearing. Since you have to take it out to remove the differential, it may save you time and money. While I don't regret any of the work that I did, it was a slow tedious process.
 
Recently, I had a whine when I coasted and the consensus here was that it was the differential. I has already replaced the transmission filter and fluid, rotated the tires, and replaced the brake pads. I checked the fluids in the torque converter and both differentials. All had fluids that looked like swamp goo. I began with the rear differential and although it looked ok, it did have a slight resistance as I turned it by hand. The whine was still there. I then replaced the front differential. My old differential had a loose center nut on the flange that allowed it to wobble. Before I put everything back together, I noticed that the hub/wheel bearing had a slight grinding noise as I turned it by hand. I replaced it as well. To satis my curiosity, I took the old hub to a shop today to have them punch out the wheel bearing. When I handed it to the Mechanic, he immediately said, "It's toast" when he turned it. The moral of the story is that you may also check your hub/wheel bearing. Since you have to take it out to remove the differential, it may save you time and money. While I don't regret any of the work that I did, it was a slow tedious process.


+1 on that.

When i had my rear diff replaced i also had the OSR hub replaced as it was out anyway & was showing early signs of failure.
 
Recently, I had a whine when I coasted and the consensus here was that it was the differential. I has already replaced the transmission filter and fluid, rotated the tires, and replaced the brake pads. I checked the fluids in the torque converter and both differentials. All had fluids that looked like swamp goo. I began with the rear differential and although it looked ok, it did have a slight resistance as I turned it by hand. The whine was still there. I then replaced the front differential. My old differential had a loose center nut on the flange that allowed it to wobble. Before I put everything back together, I noticed that the hub/wheel bearing had a slight grinding noise as I turned it by hand. I replaced it as well. To satis my curiosity, I took the old hub to a shop today to have them punch out the wheel bearing. When I handed it to the Mechanic, he immediately said, "It's toast" when he turned it. The moral of the story is that you may also check your hub/wheel bearing. Since you have to take it out to remove the differential, it may save you time and money. While I don't regret any of the work that I did, it was a slow tedious process.
+1, tranmission whine on my Transit turned out to be a wheel bearing.
 
My OS wheel bearing only whined when taking left hand turns but guess this was just early symptoms? My diff was most noticable on overrun at first then turned into a nasty grinding noise.
 
Possibly, but there is a lot of background noise in a Transit:eek:

Wheel bearings are constant because of the weight of the car being constantly applied to them. Diff bearings come and go according to load. That is how you tell the difference. You need a trained ear Keith. :):)
 
If you feather the throttle and had the diff almost free wheeling , Meaning no acceleration or decel. Then the whine occurs it is most deffinity the diff pinion and crown.
 
Is Ashcroft's the best place to go for a new one?

I'm not keen on just swapping it out for a scrappy one that I don't know is good.

Also, do we have a preferred brand of UJ parts? I thought I might as well change the UJ whilst I've got it apart...I like to fit as OEM or as good as I can afford really.
 
Have to say that I have a whine from the rear diff and have been meaning to do something about it for the last 60k miles maybe next year:biggrin1:
 

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