VCU seized?

Hi Guys.

Just had my winter tyres fitted, Goodyear Wranglers all round, then did a trip to Exeter & back today from cornwall and noticed a weird new issue. When accelerating hard, im getting a clunk from the rear, happening mostly for instance when coasting upto a roundabout, foot off the accelerator, then when I accelerate I get a clunk from the rear. Seemed fine before the tyre change, and all tyre pressures are equal and fine. Is this normal under such circumstances? Never noticed it before, but previously the front tyres where really worn and the rears not as bad. Now all four tyres are changed it's happening alot, and I can replicate it every time by coasting then applying power. I'm not talking about flooring it, literally just catching the revs to speed up. It's a 52 plate Auto TD4 with 57000 on the clock.

It feels like either the 4wd is kicking in when it's not required.

Thanks in advance

sounds more like a diff mount

caravan doctor said:

sounds more like a diff mount

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How best to check that? Get it up on a ramp and check for movement?

Oh ****, think I might have figured it out. MOT was last week and I got an advisory on rear exhaust mount corrosion. Think that could be knocking? :doh:

As stated above, would put my money on the front rear diff mount. Easy job to do and cheap. Do a search on the site on how to check and change.

Will do, thanks for the heads up. And if it's the exhaust mount I'll escort myself out of the building, didn't make a link between the advisory and the knocking.

failed centre rear diff mount eggsample: [nomedia="http://www.youtube.com/watch?v=IoHMz2ItMLE"]YouTube - Land Rover Freelander 1 2001 v6 Centre Diff Mount Fail[/nomedia]

sounds also 2 me like rear centre diff mount shot ............

yep sounds the same as i had on mine front center diff mount get the landrover one not britpart should take about 1/2 hour to do i think there is a how to on here somewhere

Just been under the car and checked all the mounts. Seems to be very little play in them. Any sure fire way to tell if it's the diff mounts? They look in fairly good nick, and the car has only done 57k

you need to get underneath the car and push the prop up you will soon see if the bush is gone

Should it be able to move upwards at all? Just been under the car and the prop seems pretty solid when pushing it and trying to move it side to side, up and down.

There will be a little movement even in a good one, but not as much as the failed one in my video above. Mine failed at about 23k miles. Take it off and have a look at it your really not sure.

There is three centre one normally go's first [its a bastid to repace] the other two is easy . . . . . .Gets Porky to fix em [eeze er furra bread]

Jodsclass said:

Just been under the car and checked all the mounts. Seems to be very little play in them. Any sure fire way to tell if it's the diff mounts? They look in fairly good nick, and the car has only done 57k

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are there any marks on the underbody where the diff input flange has hit touched?

austen said:

are there any marks on the underbody where the diff input flange has hit touched?

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I'll get underneath again later today to check for any signs of contact. Need to get this sorted in the next week as I'm due in Scotland for christmas with the family, and they are buried under snow so the Freelander has to be in good shape.

Jodsclass said:

I'll get underneath again later today to check for any signs of contact. Need to get this sorted in the next week as I'm due in Scotland for christmas with the family, and they are buried under snow so the Freelander has to be in good shape.

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while under there get a lever and check the 4 rearsubframe mounting bolts, the captive nuts become loose and the subframe can become loose.

OK Just been underneath. hardly any play in the diff mounts, slight movement in the propshaft mount behind the VCU but not much in the mount forward of the VCU. by movement it's probably less than 1cm Max. Can't see any signs of contact on the underbody. Diff seems really sold, can't get it to move much at all within the mounts.

Here is a pic of each side of the mounts rear to the VCU




And forward of the VCU




And a picture of the Diff itself and the mounts I checked for play/underside contact



Doesn't seem to be any obvious signs of contact or play in the rubber mounts/bushes