No 4WD in Reverse?

Dont know about centre diff lock...I doubt it.
Both front wheels in drain, both rears on firm gravel.....oldbaz.

Hi David,
I am intrigued, can you name some make/models that do this ?

KiwiKia

Look Here http://www.aa1car.com/library/4wd_locking_hubs.htm

Thanks David but that article only refers to rust or mud interfering with the locking mechanism and preventing it from working. I have had that happen on one of my vehicles - poor mtc by me. I now grease and repack them every six months as the vehicle is in water regularly.

In my experience if a hub spring is rusted up it will not work in forward or reverse. I have never come across any hubs that only work when going forwards.

There are many stories by people who have been told by someone's grandfather that auto hubs are dangerous and can fail when reversing or backing down a hill after a failed hill climb. It's never happened to me or anyone I know personally.

It has happened to me. My old auto hubs when reversing will unlock then lock again.
It can make for some interesting noises when climbing a hill and you lift a wheel causing the wheel to overrun the shaft causing the hub to unlock, then unlock then lock again with associated banging/clunking noises.
Failing to proceed, selecting reverse and trying to back out will also cause the rear wheels to spin before the front hubs have unlocked and then locked into reverse.

Descending a steep hill if you lift a back wheel can make the wheel over run the hub causing it to unlock with exciting results too.
The hubs are actuated by the drive shaft rotating in the middle of the hub and relative differences in hub/shaft rotation can cause them to unlock, but it is usually only momentary.
That's why I went manual hubs.

As for the Escape, aren't they front wheel drive with a torque on demand system to the rear so have fixed hubs?

Do they have a viscous centre diff or is it lockable?
If its a viscous diff, then all torque could go to the front wheels as it might have been just too hard to haul it out of the rut.

Cut an past from the article...

Some automatic hubs don't engage in reverse, and others use a vacuum diaphragm to engage the hub...

Cheers
David

Thanks for that info Hoyks, can you tell me what brand your hubs are ?

I have manual hubs on the Troopy and my Pajero has it's own rather unique one on permanant and one auto system.

Mine were the standard Nissan auto hubs on a Terrano II. They look from the outside very similar to the ones that were used on early Pajeros, they might even be the same.

They are different to the auto/manual lock ones that are fitted to Patrols.

Now I have AVM manual hubs.

Hoyks

I am not familiar with that vehicle, but that would def be the problem.

David