Slight Whine

[huesey1974]

Hi guys,
Ive been doing a lot of motorway miles in the last week and i have noticed a slight whine that increases with speed, I cant really hear anything until about 55mph and its drowned out at about 75mph.Im sure its coming from the rear end of the car and was hoping for some advice.I was thinking of changng out the diff oil as the car has loads of history but nothing saying the diff fluid has been changed.Any advice greatly appreciated.
Thanks

 

[Ted]

If you DO change your diff oil, ensure that you can remove the filler plug before removing the drain plug.

 

[BEJ]

Possibly diff pinion bearing.

 

[Uncle Fester]

Have you tried driving the car without your mother-in-law in the back?

 

[huesey1974]

haha she wouldnt fit as her ass is too big!!!!

 

[andy27168]

Hi,
I would be more inclined to think you might have a rear wheel bearing going.

 

[Vlad]

Cheap tyres on the back?

 

[huesey1974]

hmm, tyres!! they are brand new but i had them on my bmw and were awfull in the wet although it was a few years ago now.these seem to drive ok but are a little noisy, would they cause a whining noise? defo doing diff oil but this will be my next target.
thanks

 

[Dichtung]

A very common fault with many MBs , especially W201s and W124s. They start whining after about 80/90k miles just at certain road speeds; and pedal pressures.

Nothing to worry about, but can be fiixed if it gets on your nerves.

 

[Burger]

Cheap tyres on the back?

Doesn't have to be cheap tyres, just something different that for one reason or another is incompatible. I have a distinct whine on certain road surfaces in my SL that was never there before I changed the rear tyres from Pilot Sport 2's to 3's. £300 a tyre, and they make the SL whine. So, if the tyres were changed recently, cheap or otherwise, that's the first thing I'd suspect.

Regards,

 

[Ray46]

I had one chinese tyre on the rear of my W203 when I got the car (2nd hand).
At first suspected the whine was a rear hub bearing although the whine would neither increase nor decrease when loading the bearing (hard cornering both sides). The remaining tyres were well worn so I had four new firestones fitted
No more whine.

 

[Dieselman]

^ Common with worn tyres.

 

[huesey1974]

Hi,
Update time, Last night i changed my diff oil which was very much black and really stinks.The whine is still there, Im sure it only starts at around 50mph and cant hear it at 80, Dropped the car out of gear at 65 and the whine stayed as it was.Anything else i could look at?(might try changing the tyres to a better brand). Had a gearbox go b4 on my BMW so im hoping it aint that.
Thanks

 

[mauno]

wheel bearings. got 4 at the rear.

 

[BlackC55]

4 wheel bearings at the rear? Really?

 

[mauno]

inside and outside as per mb

 

[BlackC55]

Not at the rear there isn't. Just one sealed bearing per side. The front has inner and outer taper roller bearings.

 

[Gh3382]

haha she wouldnt fit as her ass is too big

I think you have bigger problems m8 that the noise if you have been looking at your mother in laws ass

gh3382

 

[huesey1974]

Hi Guys,
Just to update, I changed my rear tyres and all is silent again.

 

[mark999]

Interesting thread my 2000 SLK has a similar whine and I'm having the diff (and gearbox) oil changed tomorrow.
IIRC the tyres are Falken ZE912 so it could be down to these, they do tramline quite badly.
Mark