Patrol 2H-4H

The manual must be crap because mine is the same.
Without the hubs being locked there is no chance of snatching 4H on the move but with the hubs locked in then there is no prob like you have stated.
My last Patrol was the same.

I can move between 2H and 4H at any speed. - actually there was a time that I couldn't and had to stop - but normally it's not a problem at all, make sure that you are going dead straight!

Autos are a bit more touchy though, for some reason, at least that has been my experience.

When I bought my first GU in 2000 with the auto locking hubs, I remember the same issue. It didn't matter what speed I was doing (right down to about 5k/h), there is no way the transfer case would let me move from H2 to H4 on the fly if I hadn't manually locked the hubs in......even though that's what the blurb said I could do.

I've since learnt that (apparently) if you stop and engage H4 (with hubs still in auto position), then once you are driving it is indeed okay to change from H4 to H2 and vice versa on the run. This is because even when you change back to H2 (on the fly), the front drive train is still moving.

When I think about what I was trying to do (and what you have been trying to do too....); it was never going to work.....

Picture what is happening under your rig when you're driving along in H2 under normal conditions. Your rear tailshaft is spinning, sending drive to the rear wheels. The front drive train is idle (tail shaft, diff and axles all sitting there doing nothing). It would be stupid (of me) to think that I could pull the stubby lever back on the fly and INSTANTANEOUSLY make the front drive train go from DEAD STILL up to matching the speed of the rear drive train! It just ain't gunna happen!!!

Anyway, for me the problem is solved..... I installed manual locking AVM hubs.

Roachie

Fellas,
I regularly "snatch" the lever into 4H when on the move. EG when crossing a sandy patch that gets worse or mud that becomes serious. The hubs are always in "Auto". I reckon that I have always achieved 4WD using this method (although Roachies thoughts make me wonder if I did). I can't recall any situation where the front wheels lost traction after snatching the lever, but then again that LSD is pretty good on the rear wheels.

I have asked this question before and never really got a good reply: "What does the locking of the hubs actually achieve on an Auto Locking System?" I don't believe I ever suffered from the hubs becoming "unlocked". But then again I am no expert. Any ideas?

Kingo

HI All,
I hav e a GQ patrol and I have no problems going in to 4H while moving. I only ever do it at slower speeds otherwise you do throw a lot of instant presure on the drive system.
I read up in the Gregorys manual whcih explains how the auto hub works. hopefully I can explain it...
When the hub is in auto the front wheels spin freely - no drive.
when you put the car in to 4H, you engage the transfercase which then engages the front drive system to the front diff - the front axles then turn which activates an internal locking mechanism in the auto hub and engages the front wheels. there is an internal spring/locking system that disenages when you take the car out of 4wd and THEN drive the opposite direction to release the auto hub, I think its about 50cm. you will hear a 'click' from the hub as the dis-engage.
Now, when you stop and reverse while in 4wd, everything goes in the opposite direction and the auto hub actually dis-engages momentarily as the front axles turn the opposite direction to re-lock the auto hub in the opposite direction.
so once again to dis-engage the front auto hub, you take it out of 4wd and then drive in the opposite direction to you were just going to release the internal locking system.
thats why in the nissna car manual it advises you must go the opposite direction to dis-engage the auto hubs.
if you manually engage the hub you manually lock the system together.
if you have ever pulled your hubs apart to re-grease them you will understand what I mean about the internal spring system and see how it locks/unlocks in auto mode.

hope I have explained it all ok..

regards
Bryan

Have had 2 gu manual patrols both go into and out of 4wd high range on the move with hubs in auto no problems at all,

Hi, My Gen1 Pajero has auto hubs , but I must stop and select 4H andtake off, then I can go back to 2H and back to 4H when I need it , it wont go into 4H unless you connect the hubs first,
Cheers Des.

For quite a while after buying the GU I thought I could not change on the move. But as you say the book says you can so I kept trying. After a while I found I could do it if I got it "just right". Now I can do it without thinking.

So is it me or is it the car. Maybe its a bit of both.

Duncs

hi henpecked ,
I have a late GQ with auto front hubs ,I run then in auto mode and have always been able to select 4H on the fly up to 100 kph
cheers mechpete ,

Some extremely useful postings re the 2wd to 4wd issue. My manual was just the same!
Thanks guys, from a relatively new Patrol owner from UK.