Super Select 4wd System.

[Bitsamissin]

Ok lots of people have asked this question and fair enough to, the Mitsu super select system can originally appear complicated and hard to understand but once you look at it in depth it's a fantastic piece of automotive engineering. But it does have it's problems mainly with the dreaded flashing light syndrome which is usually linked to an electrical issue.

Basically the front diff is permanently locked to the left hand (shortest) front driveshaft.
The right side driveshaft is disconnected from the diff but will spin because it's locked to the wheel when in 2wd.
So in 2wd both front driveshafts, diff and propshaft will all spin when in 2wd.
There is a vacuum operated free wheeling hub that is attached to the right side of the diff housing. When 4wd is selected vacuum pressure is released from the vacuum storage cannister (located on the right side of the diff housing) which allows the piston to extend engaging the free wheeling hub. This locks the right side driveshaft to the front diff.
If the ignition is switched off engine vacuum is depleted and the piston will retract diengaging the free wheeling hub so the right side driveshaft will be disconnected from the front diff.
Remember there are no manual hubs on this system just wheel hub flanges which bolt the driveshaft to the wheels.
The fitment of manual hubs will prevent both front driveshafts and diff permanently rotating when in 2wd.
There are 2 electrically operated solenoids (located on the drivers side wheel arch in the engine bay) which feed/vent engine manifold vacuum to the free wheeling hub located next to the front diff.
My advice to Paj owners who are confused about this system is to buy a Gregory's no 510 as it explains it quite well.
Also the fitment of manual hubs will extend the life of the front running gear (CV's, boots etc) especially for those that have cranked their torsion bars to achieve more ground clearance.
If there is a mechanical problem and you loose front wheel drive (when in 4wd) you are the same as if a part time system has malfunctioned.
Manual hubs gives you a little scope here if you blow a front CV you can disconnect that hub to stop the driveshaft spinning when in 2wd.
Any Aisin type manual hub found on early or base model Paj's or Triton will fit onto a super select Pajero. It's a 20 min job, just unbolt the hub flanges and bolt on the manual hubs.
Also a NM onwards (Gen 3) Pajero cannot have manual hubs retrofitted as the hub flange is one piece (ie - not bolted to the wheel hub).

[PAJMAN]

Thanks for that info, explained it very well. Is there any strength issue with any of the variety of manual hubs that can be fitted and are the splines the same for all manual hubs? Interested to know as I am thinking of fitting them to mine.

[Bitsamissin]

Yep I'm 99% sure all the outer driveshaft splines are the same.
I fitted factory Aisin hubs sourced from a wrecker from a base model (poverty pack) 2.5 diesel 92 Pajero no probs. Cost me $150 for the pair.
I would only recommend the Aisin type they are steel bodied and the covers are bolted on. The two aftermarket brands are AVM and Superwinch which have plastic covers fixed with pissy allen key bolts. I had AVM manual hubs before and stripped countless allen key bolts removing the covers as they wouldn't disengage at times. They were almost twice the price of the Aisin ones.....................The guts of the Aisn hubs are much beefier to, spring, hub collar etc.
I'm pretty sure Triton Aisin manual hubs will fit a Pajero as well.

[PAJMAN]

Thanks again for that, I think free hubs may be a good idea with the air locker - waiting, waiting

[Bitsamissin]

Front locker RD110 will be available Feb 04 so I'm told

Frank.