Thread: Signs a rear propshaft centre bearing needs replacing

Fair enough, new propshaft 653 aud plus the fitting kit plus freight and ir easily gets to 1k. I wonder if people bother to accurately mark the installed position before removing, as these shafts are most likely dynamically balanced. I would be looking at getting the original shaft rebalanced and I would do the bearing, uni joints and re grease the splines all at once.

Originally Posted by kelvo

Just replacing the centre bearing seems to be false economy, as they don’t seem to last. Many UK independent LR garages will only replace the complete shaft. Lots of threads/FB posts complaining that the bearing has failed after a short time when only the bearing has been replaced, regardless of bearing make/quality.

There also could be something else worn or out of balance that is causing the bearing to fail prematurely.

Replacing the complete shaft is definitely piece of mind if the vehicle is being kept for the long term.

Originally Posted by 350RRC

Didn't that usually trash the transfer case?

A minor issue in comparison these days, with the 'beloved nuances' of D3's and 4's'.

DL

Transfer case? I wish.
When mine went on my D2, it took out the entire transmission.

Thanks all for the thoughtful replies. It’s important to note that at this point the vibration is only slight, only on little acceleration, only at freeway speeds and only noticeable on a smooth road for the first few minutes. Also seems to be more noticeable in the early morning, hard to pick up in the evening.

So to my original question, how much deflection is normal / ok for the shaft at rest using only my hand to push and pull?

happy to replace if the rubber grommet is too soft and close to splitting, but don’t like replacing things Willy Molly without proper diagnosis.

I think you’ve got your answer. We don’t know and are only guessing, so maybe take it to an LR specialist and ask them?

Of note, from the manual:

The front and rear drive shafts are not serviceable items and a failure will require the replacement of the completedrive shaft assembly.

And, with respect to the bearing:

Shaft Bearing Assembly
The shaft bearing assembly comprises a pressed steel housing, a rubber diaphragm and a ball bearing. Thediaphragm is bonded into the housing. An internal metal ring, bonded to the bush, allows for the bearing to be pressfitted into it. The rubber bush allows for small deviations in alignment and also absorbs vibrational forces. The shaftbearing assembly is located by screws, which pass through plain holes in the bearing assembly and locate into nutswelded on the inside face of the chassis cross-member.

That doesn't sound like something you should be able to get 3 to 4 cm of movement by hand on...

Thanks JPVD,
the bearing is fine, no movement, the rubber bush/ grommet surrounding the bearing is where I can force the movement, and not 3 to 4 cm, but certainly 5 to 7 mm in each direction.

I would expect some deflection as it’s job is to absorb vibration. I just don’t know how much is too much, or if it’s fine and the vibration is coming from elsewhere.

Originally Posted by BushDisco

Hi distinguished forumites, I've noticed in recent months that when on a freeway and coasting or under very light throttle that i feel a vibration which in my mind may be the rear prop shaft. Or not.

SDV6 4 my12 with 230k and well serviced. Wheels balanced (certainly not front wheel balance issue as I don't feel through the steering wheel).

Was under the disco today starting a fluids service so I took the cover off the rear shaft, grasping next to the centre bearing I could push and pull the shaft up and down, getting maybe 3 to 4 cm Max movement between extremes.

Inspected the rubber bush surrounding the bearing and couldn't see any cracks or gaps. Seemed supple and intact with no obvious issues, and zero latteral movement felt in the bearing.

At $500 for a replacement I'd rather not replace if not ready, so how do I definitively diagnose a failing centre bush, or rule it out?

Cheers.

There’s a few YouTube videos on this topic if you want to do some research there. Good luck. 👍🏻🙏🦘