Lockers aint' Lockers!?

[burtbunch]

Gday All, Long time watcher, first time poster.

I have a 92 NH 4D56 TD GLS LWB Pajero. I understand the benefits and physics of lockers but, can someone please explain the way in which the centre locking diff works on my Pajero? And how adding lockers (if I need to) will change the centre setup, does it become redundant?

Thanks

Carey

"Take it Off Road or take it off the road!"

[-Scott-]

A centre diff allows the front and rear wheels to travel different distances as the vehicle turns a corner. But, like any diff, it will allow all drive to go only one way. With the centre diff unlocked one spinning wheel can rob the vehicle of all drive - one wheel spins, the others don't.

Locking the centre diff means front and rear axles will both get drive all the time.

However, standard "open" diffs front and rear mean that one front wheel and one rear wheel spinning at the same time can strand the vehicle again. A "four wheel drive" looks like it's only driving two wheels.

Adding diff-locks to front and rear axles doesn't make the centre diff lock redundant - if you lock front and rear, but not the centre, then all drive could be sent to one end of the vehicle. That is, one pair of wheels spin and the other pair doesn't.

Adding an auto-locker to the front of a Super Select vehicle affects the front diff operation. Typically, owners install manual free-wheeling hubs.

How's that?

[burtbunch]

Thanks for that. So if a front locker is substituted with manual hubs what difference is that to the current setup with auto hubs? If you have a locker on the rear and cntre locked and you loose traction on one wheel at the front won't you still loose drive at the other front wheel? In a situation where there is little traction is there a need to have all three locked? Say I am trying to climb a big dune if I have centre locked and I lose traction on one wheel front and back I am stuck right? No Drive. If the rear has a locker I still have drive at the rear. If the front has manual hubs instead of auto I don't see the difference that would make coz the front diff is still unlocked.

Sorry to be a pain but I just have to get it straight in my head!!!!

Cheers

Carey

[-Scott-]

OK, I shouldn't have added the bit about manual hubs. That ONLY applies to a Super Select vehicle with an auto-locker on bitumen. Offroad, lock them and forget them. (An auto-locker is more accurately and auto-UNlocker. The diff is locked until one wheel tries to travel further than the other, when it automatically unlocks. A "conventional" locker, like ARB Airlocker or the factory locker, are switched by the driver.)

Once you lock your centre diff you need two wheels spinning, one on each axle, before you lose all drive. You MUST have one wheel on each axle turning.

If you lock your rear diff too, you MUST have one front wheel and BOTH rear wheels turning - so you need three wheels spinning before you lose drive.

Any clearer?

[burtbunch]

Yes thankyou.

Much appreciated.

What options are avilable for these locking diffs. Auto? Manual? ARB is the only name I am familiar with. Are the costs in the thosands? Do they need to be professionally fitted. I am reasonably confident with the tools but don't have any specialist equip. Have stands etc. to raise the vehicle. I have just spent $4,5oo gettting a lot of engine repairs done to restore power but is all useless if I can't actually use it well off road.

Had new injector pump, injectors, harmonic balancer, timing kit as well as a few other bits and pieces. Hope she goes a bit quicker and uses less fuel now!! I was only getting 500 k's to a tank around town! was blowing sh&% loads of black smoke and running like a pig!

Thanks again for your help.

Carey.

[ROGQ]

http://www.pps.net.au/4wdencounter/arti ... locks.html


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