Ok the rear rumble has struck with 60k on the clock....

Click image to enlarge

Have seen this one before

Do you have the special tools available?

No i had it sorted local to me in west sussex.. 2011 SD4 XS

Is there a technical reason to explain this 'pattern' of failure.
Why are there no radial scratches on this roller bearing.
Has it had excessive end load, whilst stationary.

And more importantly, is there a way of avoiding this. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 76k+ miles) (MY2015)

metal ive seen the past in other things that looked like that has been the result of surface corrosion and then being cleaned/polished off.
But I cant see how the nose bearing would get surface corrosion so is it poor quality surface finishing by the manufacturer which over time has been damaged and 'polished' by the rotation of the bearing ?

The bearing must have been in contact with oil so that should rule corrosion out. It could be material fault or the local stress exceeds the strength of the bearing.
I read from other threads that after lots of diff bearing failure LR had to upgrade the diff. bearing to later Freelander 2 which make me think that the original diff. bearing had been under calculated for its strength.

I must admit that the pattern made me ask about corrosion and thinking back when I first saw the car before buying there was a fair bit of green growing on the car hinting that it had been stood for a time.. 2011 SD4 XS

Last edited by Brainzzz on 22nd Sep 2017 5:13 pm. Edited 1 time in total

Brainzzz,

Are the four marks shown the only marks on the surface?

Can you take a picture of the other side?


Here is a link with different failure modes for bearings

http://www.skf.com/cn/en/products/bearings...index.html


Thanks for sharing

Paul

Its all about the money. Poor quality case hardening will be one factor. FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

p_gill wrote:

Brainzzz,

Are the four marks shown the only marks on the surface?

Can you take a picture of the other side?


Here is a link with different failure modes for bearings

http://www.skf.com/cn/en/products/bearings...index.html


Thanks for sharing


Paul

just found time to get the rest of the bearing pics done..

Click image to enlarge

Click image to enlarge

Click image to enlarge

Click image to enlarge

 2011 SD4 XS

Brainzzz,

That helps a lot.

Because the damage is isolated to only 1/4 of the race I suspect that one of two things happened.

1. During the install a misalignment of the tooling caused the rollers to damage the race

2. The damage occurred due to inadequate lubrication and vibration induced static loading


If cause #2 is the source of the damage then I would want to know the following

I. Was the Haldex/Differential Unit pre-assembled and shipped by rail? How far?

II. Was the Differential filled with Gear Oil prior to shipment?


Assuming the answer to the first question is yes, from Sweden to the UK and the answer to the second question is No, the gear oil was added in the UK not Sweden. Then the vibration from the Rail journey may be the source of the damage.

Note: if you were to inspect the bearing after the rail trip I suspect the marks would be very small and difficult to see and that they just get deeper over time.

Here is a link (see wear by vibration)

From SKF "Bearings in machines transported by rail, road or sea may be subject to vibration damage too."

http://www.skf.com/cn/en/products/bearings...index.html

The good news is that if Rail transport induced vibration is truly the cause of the failure then replacing the bearing should result in a much longer service life for the second bearing. (I'm not planning to send my differential dry by rail after a rebuild)

Thanks for sharing the pictures its very helpful.

Paul