Propshaft centre bearing

[keith of kent]

Car is 2015 S212 E350 56k miles . Full MB specialist service history.
I have a bearing type noise from the rear of the car which increases with road speed and is audible from 20mph on a smooth road, even to my wife! Definitely not from the front of the car, does not come up through the steering or pedals. Not engine revs related.
Having the 4 wheel tracking done on a Hunter setup I asked the technician if the car has a centre bearing on the propshaft. He showed me that it had and he was able to lift the propshaft up and down just to the rear of the bearing, it hade an audible knoking sound when he did this.
I then took the car to my trusted indy who road tested the car and could hear nothing wrong, put the car on the ramp and said that the movement is normal. Took it to the local Mercedes dealer who could hear the noise immediately at 25 mph but then they want £189 to carry out a preliminary investigation.
Can anyone tell me whether up and down play at the centre bearing is normal as I'm sure it can't be?

 

[Petrol Pete]

On many models the 'solid' roller bearing is moulded into a rubber 'hoop' that is fixed in the metal half ring that bolts it to the car. There will be some 'play' at in this are to help with alignment of the drive shaft (which telescopes at this point) .

I can't see how this bearing is toast at just 56K miles. But if it's knocking something is not right.

 

[Trickythemerc]

Could be tyre noise, I had something very similar and it was tyre noise. I asked my indi to check the centre prop bearing and he said they rarely fail.

 

[keith of kent]

I bought this car when it was 18 months old at 12K miles from a MB main dealer. The noise has been very gradually coming on for 2-3 years, at first so slight I thought I was imagining it. It has gone from Contisports to Michelin Pilot Sport 5's so the tyres are not the cause.
I am not a hard driver so the car has had an easy life.
I'm taking it to another MB indy tomorrow, I will update this post with the findings

 

[W1ghty]

I would assume your Indy is a wealth of knowledge on MB’s , and he can find no issues . I think you will just be throwing money away at MB .
Why not just get your Indy to replace the centre bearing ? Rather than pay MB for the hours investigating?

 

[grober]

https://mercedes.7zap.com/en/eu/fg/car/e-klasse/e+350+cdi/d01/212023/fg/0/0/41/0/015/0/0/

THE PROPSHAFT CENTRAL BEARING IS MOUNTED IN A CIRCULAR RUBBER RING IN A BRACKET BOLTED TO THE FLOORPAN. THE BEARING ITSELF IS USUALLY OK ITS THE RUBBER MOUNT THAT GOES. THE PROPSHAFT IS ALSO DYNAMICALLY BALANCED BY SMALL METAL PLATES WELDED TO THE SHAFT- IT WILL VIBRATE AT CERTAIN SPEEDS IF ONE OF THOSE IS MISSING

 

[ALFAitalia]

No need to SHOUT!

 

[ernie]

No need to SHOUT!

He doesn't normally shout! I guess the caps lock was on and he didn't notice till he had finished typing!

Ernie

 

[Petrol Pete]

https://mercedes.7zap.com/en/eu/fg/car/e-klasse/e+350+cdi/d01/212023/fg/0/0/41/0/015/0/0/

THE PROPSHAFT CENTRAL BEARING IS MOUNTED IN A CIRCULAR RUBBER RING IN A BRACKET BOLTED TO THE FLOORPAN. THE BEARING ITSELF IS USUALLY OK ITS THE RUBBER MOUNT THAT GOES. THE PROPSHAFT IS ALSO DYNAMICALLY BALANCED BY SMALL METAL PLATES WELDED TO THE SHAFT- IT WILL VIBRATE AT CERTAIN SPEEDS IF ONE OF THOSE IS MISSING

See post #2 for similar.

 

[keith of kent]

Yesterday I went to a different Indy. During a test drive he could hear the noise at 30mph on a smooth road. With the car in the workshop and on a hoist with the wheels clear of the ground he drove it to a high speed, I was in the car and the noise was very evident as you might expect at 150mph!
With the engine idling and in Drive we observed from outside the car that the rear tyres were running out of shape, but not the tyres, both the rear wheels have runout on them both in circular and sideways planes.
Obviously when we ran it with the wheels off the ground there was no damping effect from the tyres, and also because the air suspension let the wheels hang down there is no damping effect from the suspension either.
It's great to know that the car is not suffering from imminent diff or other mechanical failure.
He said he can get the wheels refurbished/repaired at a cost that seems reasonable, I think that would be advisable as out of true wheels will wear the tyres/suspension/wheel bearings as well as the irritating noise.
So in future I will be taking the E350 and the GLA to this Indy; his name? Steve at Stevensons near Maidstone

 

[keith of kent]

I took the car to Steve Garlick and was lent a set of wheels whilst they had mine refurbished. The loan wheels were a matching set with Pirelli matching tyres all in good condition. When I drove home with these wheels the noise had gone.
Today returned there to have my wheels refitted, a really nice job had been done, the wheels look like new, and the noise that started all of this had gone. The cost to do all 4 was £450 incl vat.
Top service and I will be returning with both our cars