V8 diff lock

[Matt_H]

James has just bought a 3.9 auto V8 rangie.  No sign of any diff lock. Does it have a diff lock or some kind of viscous thingy?

Matthew

[muddyweb]

If the transfer box lever only has hi-lo on it, and no side to side movement, then it will be a Viscous coupled box.. (no manual diff lock)

[Matt_H]

aye that's the one.. so is the viscous any good compared to a manual diff lock for off road use?

[muddyweb]

I'm not a fan, I prefer the manual control... but they seem to work well enough.

[ratman]

Having used both in the mud as it were the only difference is the cost when they go wrong.

The manual boxes are cheaper

[Range Rover Blues]

There is supposedly less backleash becuse the B-W box uses a planetery gearset on the first motion shaft, so in high ratio the box is stalled and power is transmitted direct to the Morse chain and so to the centre diff.  In low ratio the gearset spins around the first motion shaft before transmitting drive to the chain.  They were intended to be quiter and as I say have less backlash to suite our American cousins.

I'm quite happy with the performance but then there are other much more experienced off-roaders in the club.  I suspect it may use slightly more fuel due to the drag and possibly wear tyres a little but as has been said, it's the cost when it busts.

[oakeedokee]

I'm fairly new to having a Rangie. Mine has the Viscous coupling, which incidentally is great off road as it's one less thing to worry about, however my question is does it need any servicing? Does the viscous fluid need topping up or changing or anything?

[Range Rover Blues]

The viscous unit is sealed for life.  It just needs changing every 2 years (etc etc as per handbook) with Dextron3 or whatever.  Ours has EP80/90 in it for nearly 2 years, plus an additive and it's done it no harm at all.

[oakeedokee]

:? sealed for life but needs an oil change every 2 years? Now I'm confused! :?  :D

[landyman Ash]

The visocus unit gives you diff lock ONLY when you need it, which is great.

DOwn side is that whens its broken, take you a while to notice and then your stuffed!!!!

I run viscous and love it but its a personal chouice thing

[Range Rover Blues]

:? sealed for life but needs an oil change every 2 years? Now I'm confused! :?  :D

Sorry I wasn't very clear, the viscous unit is sealed for life, the T-box needs servicing as normal.

One other advantage of the viscous unit is on the road, it removes the tendancy for Rangie to understeer in the wet/snow/ice because it stops the front end 'spinning out'.  This was noted at the time of it's launch by UK journalists.  I have to admit if ours looses grip it does it on all 4 wheels :?