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Center Diff issues

Richard Jackaman

Well-Known Member
Apr 6, 2010
I've got a 1995 24V 4.2TD VX Manual cruiser. Not had it long, just a couple of weeks but have noticed that the transmission seems "tight" when driving on normal roads.

Today, when I had the front wheels off to service the brake calipers, I tried spinning one of the wheels. When only one was off the ground it wouldn't turn. Tried in gear, out of gear still no movement. When both were off the ground then the other wheel turned in the opposite direction to the one I was moving.

Tried putting it in gear and gently releasing the clutch with the engine running with both fronts on axle stands and seeing if the fronts would spin but it just tried to push off the stands with drive to the rear.

I don't have the optional hi range diff switch fitted.

To me this points to the center diff not freeing correctly.

When I select low range the center diff light comes on and the ABS shows as being off. The center diff light doesn't light when I start the ignition in hi range. Not sure if it should.

Front and rear diffs seem to engage correctly, light solidly on, and off when de-selected.

Does anybody have any suggestions as to what can be causing this behaviour. I understand that the VX has a viscous diff. Could it be running on the wrong oil?

Should I be able to hear the centre diff engaging/dis engaging when put into low range?

Things to check?


Does it feel tight round corners or squeel the tyres unexpectedly on roundabouts? The viscous coupling can fail and behave more like a locked centre diff in which case you can remove the VC and use the truck without it. Both wheels off the ground turning in opposite directions is normal BTW.
It does feel tight when cornering and wheels sometimes skips when doing 3 point turns etc.

Is it possible to repair the VC in the diff or is it something I'd have to get replaced off another vehicle?

I'll have a look in the service manual.

Somebody suggested that if the transfer box had been filled with the wrong oil it could become sticky ie. not 75w90.


Richard Jackaman said:
Is it possible to repair the VC in the diff or is it something I'd have to get replaced off another vehicle?
The VC is a sealed unit and needs to be replaced, rather than being repairable, as far as I know. As mentioned previously, lots of other models do not have the VC, so you would be fine without it - the VC falls into the "nice to have" category but not essential at all.
I have seen mention on other forums that a new VC is not a cheap item :?

Thanks for the advice, doesn't seem so bad as I initially thought.

From the links supplied and other reading on the net it appears that the VC acts like a sort of LSD between the front and rear propshafts and that removing it will give me an open diff in the middle for normal driving. When I get round to fitting the diff switch I'll be able to lock the centre diff in hi-range for driving in snow etc. Just like on my 70 series cruiser.

Obviously it's a nice to have and would be worth refitting if I could get a used one but I think I can live without it. In fact until yesterday I didn't know that that was what the VC did.

Just need to get some sealant so I can do the deed later on in the week.


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Re: Center Diff issues -UPDATE

Well I removed the VC and must say what a difference in the driving experience. No longer feels tight when cornering and gone is the tyre skipping when maneuvering.

Was a fairly simple job to do for anybody with the same issues. Took about 3 hours. Only difficult bit was, as mentioned in the writeups, getting the circlip off the rear output shaft to remove the VC unit. The VC itself was locked solid. Apparently the previous owner had had it in to Mr T a couple of times to rectify the skipping issue but they could find no fault :o

Other forums mentioned getting more transmission noise/clunking but so far I haven't noticed any.


Might improve your MPG as well if it was that bad :)