Locking? viscous coupling centre diff

Need help on this one. Range Rover from October 1988 thru to 92? have a viscous coupling centre diff. Question; is it possible to modify this diff to include a 'manual lock' [as per 1970 thru to 1988].

I have been informed that you can only modify the later Disco's centre diff to manual lock. If so, will a later Disco diff bolt into a 1990 RR?

Any info or where abouts I can obtain would be appreciated. Thankyou in advance. John Milburn.

Reply to
Milcom Instrumentation
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The only way to fit a manual locking centre diff would be to change the transfer box.

Reply to
SimonJ

On or around Mon, 25 Aug 2003 08:55:05 +0000 (UTC), "SimonJ" enlightened us thusly:

quite. You'll need the rear propshaft as well, the manual transfer box (LT230 type) is 2" longer front-to-back than the Borg Warner one.

and why?

Reply to
Austin Shackles

I'm about 95% sure :-)

I seem to remember that when I put the auto box in my Rangie, replacing the 5 speed manual with LT230 with an ZF auto/BW transfer, I fitted the rear prop Ok but when I came to fit the front prop shaft it was about 2 inches too short which led to an hour or so turning the garage upside down trying to find one that would fit... It could have been the rear but then that would mean that the handbrake drum would have been 2 inches further forward and I find that unlikely as I had to drop the back of the gearbox to change the brake shoes last weekend.

cheers

Dave W.

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Reply to
Dave White

The phrase "returned" suggests that they were using a none manual locking diff...

The Disco's never had the viscous diff, the ones without a diff lock had an LT230 without a lever to operate the diff lock. They always had a manually locking diff but on some models/ages there was no way to operate it. The traction control system was used as a substitute for a locking centre diff. I have no idea why they didn't use a viscous diff or which arse at Land Rover came up with the idea but there you go...

On most Disco's you can retrofit the necessary bits to operate the diff lock although I have heard (but not seen) of some where the diff housing has the actuator hole blanked off in it's casting rather than just a plate over the top of it.

They are going back to having a diff lock lever because someone realised what a stupid idea it had been in the first place to fit a manually operated center diff without an operating lever. Officially LR claim that the traction control couldn't cope with a locked centre diff but I suspect that's bullshit as admitting that they'd dropped the parts to save a fiver was too difficult.

cheers

Dave W.

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Reply to
Dave White

To my knowledge there has never been an auto-locking Disco centre diff. Recent models had the lever removed, so although diff was capable of locking, there was no control lever to do so. I think Land Rover felt that the traction control would be just as good (and in many normal situations for Disco drivers they have a point). However, customers thought differently so the lever has returned in recent models. The diff itself has remained unchanged throughout.

Tim Hobbs

'58 Series 2 '77 101FC Ambulance '95 Discovery V8i

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Reply to
Tim Hobbs

Perhaps they just couldn't get their heads around the difficulty of relating ETC producing wierd cross axle responses with the diff lock engaged before the thing went to market ... easiest solution, remove the lever then sort the ETC software out and reintroduce the lever as 'an upgrade' later ...

Reply to
AndyG

Dave White wrote

This is certainly bullshit. Hasn't the Td5 Defender always had the option of traction control with a locking centre diff? No problems there - in fact folks who have driven one tell me the combination is awesome.

I reckon it's a nut-that-holds-the-wheel thing. The Disco is a more mass-market vehicle than the Defender, driven by people who don't drive off-road regularly if at all. Disabling the difflock is the ideal remedy against the likelihood of shedloads of muppets driving it with difflock engaged for 500 miles of tarmac and then claiming for a new transmission under warranty. "Oh, we wondered what that little lever did."

I owned a 2001 Disco for a while. The dealer who sold it to me looked at me like I was bonkers when I asked him why it had no difflock. "But sir, the traction control is so brilliant it makes the difflock (whatever that is, cough) completely redundant!"

Bollocks. Having driven the car for 10,000+ miles I beg to differ. A low bank near my house which I have crossed without drama or wheelspin in a 90, a classic RR and a P38A (using difflock or letting the viscous coupling do its stuff) completely stopped the T/C-equipped Disco with two opposite wheels spinning merrily. Yes, I got LR to check it. Yes, it worked fine.

They have reinstated the difflock - but of course now it's a cost option.

DaveP

Reply to
Dave Pseudonym

Haven't had the chance to try the centre diff lock in my new vehicle yet, but I suspect we've an off road day coming up in the local Club here so will try it then, provided it's a safe course as it's my everyday vehicle!

Reply to
Llandrovers!

On or around Tue, 26 Aug 2003 11:05:34 +0100, Tim Hobbs enlightened us thusly:

There was another aspect, that by locking the centre diff you get a "4-wheel handbrake" effect, which means that you can raise the back of the vehicle on a jack without it rolling away.

Reply to
Austin Shackles

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