has anyone tried using the OE pump of a Grand Vitara to activate an ARB front air locker?

ARB uses air pressure to activate the locker.  Suzuki uses vacuum the GV pump is a vacuum pump.

ARB uses air pressure to activate the locker.  Suzuki uses vacuum the GV pump is a vacuum pump.

That's a common misconception.

Actually, the GV pump IS a positive pressure pump, but it has nowhere near the output required for an ARB locker.

Thank you for the inputs! Is there a way to increase the air pressure of the OE pump to be able to use it in lieu of the ARB air compressor?

No - the pump is way too small to develop the pressure required to operate an ARB locker.  Just in case the thought crosses your mind, the ARB pump also has way too much pressure to operate the actuator in a GV diff and will destroy it, although you might be able to use a regulator to bring the pressure down to an acceptable value.

......  Just in case the thought crosses your mind, the ARB pump also has way too much pressure to operate the actuator in a GV diff and will destroy it, although you might be able to use a regulator to bring the pressure down to an acceptable value.

The GV pump incorporates control valves to apply and relieve pressure as required, and to interface to the lamp circuit.  Though nothing is impossible, I don't think adapting another pressure source is a practical proposition.

The GV pump incorporates control valves to apply and relieve pressure as required, and to interface to the lamp circuit.  Though nothing is impossible, I don't think adapting another pressure source is a practical proposition.

ARB supplies an electrically operated air valve that does basically the same thing - flip the switch on and it allows air pressure through to operate the air locker (or diff actuator if you prefer), flip the switch off and it vents the pressure releasing the air locker (or diff actuator) - you want the 4WD light, wire it in parallel with the solenoid.

The big difference in the two setups (apart from the pressures involved) is that Suzuki turns the pump on & off to control the air pressure whilst ARB turns the air pressure on & off and completely ignores the source of the air.

With the ARB system you have a compressor with a storage tank, the compressor can be electrically driven with it's own control switch on the dash or perhaps driven off of the engine from an accessory belt drive - either way there is usually a separate pressure switch that shuts the compressor off when the tank has been filled (in the case of an engine driven compressor there will be a magnetic clutch similar to that used with an a/c compressor.)

You MUST have pressure available in the tank before you are ready to use your ARB lockers - the next step is to flip the switch for the front or rear air locker as required and that allows air to flow from the tank to the air locker.  As I mentioned earlier, you can theoretically use a regulator to reduce the pressure and then use the same electrically operated air valve to control the air supply to the front diff actuator to engage it and disengage it.

Let me put it this way - I have not yet fitted ARB lockers to my GV, although I have considered it, I have also considered adding "onboard air", but I am not willing to give up my a/c - assuming I had a source of compressed air and assuming again that the 4WD pump failed, it would be a very simple proposition for me to use that onboard air to control the front diff actuator, if it were still in place.

Thank you for a rather long and detailed explanation. One comment I would like to make regarding the switching of the Air Lockers, we were successful to do some rewiring of our own to activate the front air lockers while the rear air locker is off. We use this in off-road competition depending on the varying obstacles of the race track.

The reason why I am contemplating on this is the fact that I already have a rear air locker for installation in my Grand Vit and the front air locker is a future project I intend to pursue.

Thank you for a rather long and detailed explanation. One comment I would like to make regarding the switching of the Air Lockers, we were successful to do some rewiring of our own to activate the front air lockers while the rear air locker is off. We use this in off-road competition depending on the varying obstacles of the race track.

As far as I know, the norm is to have independent switches for the front & rear lockers, allowing you to lock which ever one you want, whenever you want.  All the installations I've seen had a compressor switch and separate switches for which ever end had a locker fitted.  I think this is the reason that ARB "switches the air" rather than the compressor - switching the air allows you independent control of the lockers with a single compressor.

I can't think of a reason why I'd want the front locked and the back unlocked, but then I have no race experience - at least - not off-road 4x4 racing.