Centre diff lock stuck on! --Help

I have a 1993 tdi Manual rangie that has the following problem:
I think the centre diff lock is stuck on. The steering has gone a bit "tight", going around sharp bend on tarmac is causing small wheel slips and my tyres seem to be wearing fast.

So I jacked up a wheels at a time with handbrake off and in neutral but couldn't rotate jacked wheels.

My older rangie was more familiar as it had a 2 function gear lever (high-low and diff lock on/off) and a dashboard light that can on when difflock was engaged but this model can only allow me to select hi/low.

I'm very worried about causing exceessive wear/damage to the drivetrain and am thinking of disconnecting front propshaft until this is remedied. Good idea?

Any ideas what is malfunctioning? Solutions?
Thanks Richard

Your model has a viscous coupling in the transfer box instead of a manual diff lock lever
I'm afraid the coupling has seized which is making you run with the centre diff locked - you will have to buy a new viscous coupling and get it changed
In the meantime you can remove the front propshaft and run about with it off to stop the transmission winding up till the new one comes
Not too bad a job to do as you can leave the transfer box in place and just remove/replace the coupling through the end plate
Couplings can be had for about £150 new if you shop around

Thanks V8kenny,
I hope I haven't done any damage, - what really brought my attention to it was a new vibration coming from the drivetrain which might be a bearing worn out etc. Time will tell. Did you say it was possible to change this viscous coupling without removing the gearbox?
Richard

Yep, no need to remove gearbox or transfer box
Once you have removed the front prop all you have to do is remove the ring of bolts holding the end plate on the transfer box
You will need to remove the gearbox mount on this side to allow clearance so just support the gearbox with a trolley jack
The viscous coupling and the bearing will slide out and you can take press the bearing off the shaft and refit to your new coupling
remember to drain the transfer box first and have some ATF to fill it back up with
Have a search - I'm sure this must have been covered in the past

Thanks again, I've done some enquiries and got quoted €650/£500 for a new viscous coupling. Did a bit of extra research and was told if the old oil from transfer box was dirty black then a sure sign coupling is knackered. Because I'm worried I've done extra damage (may have been running with no oil in there - will find out soon) I may just get a complete second hand transfer box of ebay for under £100. I've dropped a LT95 out before without removing engine - I guess much the same for the Lt77?

Drop the prop and have a run around - if everything is quite and normal sounding then I wouldn't bother changing the box - all IT will have done is wind the transmission up a bit as the front wheels will have been travelling different distances while cornering - this usually dissipates on its own
The ebay box might be worse than yours !
Here's a far better price for a VC :-

RANGE ROVER VISCOUS COUPLING BORG WARNER TRANSFER BOX on eBay, also, Land Rover, Car Parts, Cars, Parts Vehicles (end time 03-Mar-08 00:26:41 GMT)

Hi Richard. There's a shop on ebay called Island 4x4 that does viscous couplings for £43.99 or £49.99 depending on which Classic you have. They're obviously not genuine landrover parts but if you're not fussed they're cheap as chips. I've bought a few bits off them and never had a problem. Helpful guys to. Good luck mate, hope this helps.

look...

RANGE ROVER CLASSIC 3.5 3.9 EFI 89-94 VISCOUS COUPLING on eBay, also, Range Rover, Car Parts, Cars, Parts Vehicles (end time 29-Feb-08 21:22:40 GMT)

Thanks blackvoguebeauty,
I've actually bought other stuff from them years ago- good service - will use them again - thanks again Richard

Errrm, I think you will find that's the viscous coupling for the fan at that price !

My '93 Vogue had a siezed viscous coupling, I did 12k miles in it and who knows how many miles were done before that, I had no problems, no excess tyre wear, just a bit of tyre squel in car parks.

I reckoned the most likely item to go from the siezed coupling was a CV joint and they are £40, so considering what the car was worth I never bothered to replace it.

v8kenny said:

Errrm, I think you will find that's the viscous coupling for the fan at that price !

Click to expand...

O bugger! You're spot on kenny! What a tool I am! If it sounds WAY to good to be true, it definitely is!

Island 4x4 is still a good shop though... My contribution to the thread wasn't a COMPLETE waste of time and space!

Thats still a good price for a viscous fan,I've found island 4x4 to be good.Is there much chance of the failed transfere unit causing any long term damage?