can I add another tip after using the difflock it is not unknown for it not to disengage ( you do not want this if you are moving on to tarmac or other firm ground for reasons stated previously) simply stop and reverse a couple of yards and the difflock should disengage and the light will go off.
DerekW
I have also heard that if you drive diagonally off a kerb, then the wheel in the air will allow the transmission to unload, which will allow the difflock to release
Giles
True - ask any driver of a 6x6 Scammel. They don't have diffs between the axles and when on tarmac must be bumped off the kerb every 15 miles or so.
Ref 6x6 Scammell. The above statement is incorrect, at least it was on the ones I drove. The two rear wheels on one side are connected by a transmission case which then transmit the single drive drive to a centre diff with a similar transmission case on the other side. This allows the two wheels on one side to move through extreme up and down movement. You were supposed to stop and grease the propshaft every 25 to 50 miles mainly because the propshaft was right next to the large silencer box. We have driven over hundreds of miles on tarmac without ever needing to bump off the kerb. With the aid of the hand throttle lever is was possible to change drivers without stopping on some of these long trips. Keil to Herford (not Hereford in England!) was a real long one.
Alan Ex REME
The "bumping off the kerb" story is usually told about the Alvis Stalwart, but an owner I met said it's not true for that either, while it doesn't have differentials it has a dog-clutch like mechanism between wheels on each axle, pressed together with springs so it acts like a solid axle up until a point, then slips. I was told this quite some time ago and some beer may have been involved so I reserve the right to be wrong ;-)
I'm told that most 6x6 lorries (and my pinzgauer) don't have diffs between the two rearmost axles as they're so close to each other that drivetrain wind-up is minimal, and what there is gets relieved when you go around corners as the wheels have to slip anyway as they're dragged sideways.
True, and much more reliable than reversing. Putting a wheel onto a soft or loose patch has the same effect.
The bits that stick are in the linkage which is directly connected to the lever. All that is required is to move the lever to the full extent of its travel in all directions. The diff. lock itself may not engage/disengage for the reasons previously mentioned but that has no relevance to keeping the linkage free. (The lever only sets up the conditions for engaging the diff. lock but does itself not engage it.) You can usually do this whilst stationary but it may sometimes be necessary to have the engine running and to engage/release the clutch whist in neutral to get the relevant gear set engaged.
Thank you! That's really helpful information.
I shall do it more often in future...
"Ian Rawlings" wrote in message news: snipped-for-privacy@lounge.tarcus.org.uk...
I don't know what Scammell Hugh is talking about but I am talking about the Meadows petrol engined Scammell of which the British Army had a great number. There was one diff at the rear which took the drive from (or rather to) the four wheels at the rear by way of a large gear casing. As I said this allowed huge movement up and down. I had experience of this when a gear came adrift and seized up the rear completely. This disorganised the traffic for miles around and could not be moved until a big enough low loader could be found. I drove and worked on these vehicules in various parts of the world for about five years. With the 6x6 Stalwart and the others of that 601 series Saladin, Saracen & Salamander there were outputs from either side of the gear/transfer box assembly to a bevel box which then drove the three wheels on either side seperately. This eliminated wind-up because i each side could do its own thing. The hubs had an epicyclic gear driven final drive. If assembled incorrectly this lead to wind-up in the hubs because the epicyclics had to be assembled lining up the dots on the various planetry gears. Many people thought this was due to wind up in the transmission. It was possible to have all six wheels rotating when in deep mud so the dog clutch (limited slip diff type thing) locked up the drive to give a better chance of getting out. This was only fitted on the Stalwart. Question - If a Landrover is 4x4 what is a half-track? 2x 2halves perhaps!
Alan Ex-REME & MOD @ Chobham
Still 4x4, 2 wheels and 2 tracks, i.e. 4 ground contacts, all able to be driven. :-)
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