4WD, what happens?

[Mikey]

I know this will make me sound thick but what happens (mechanically) when I select 4H or 4L. I don't have a rear diff-lock so I assume power goes to all 4 wheels until one losses traction and then that gets all the power. But, that wouldn't explain why my D22 goes just about anywhere, or does the power go 50/50 front/rear so if one wheel slips say on the front both rears will drive. Would that mean there's a center diff that's locked???

Any help would be great thanks

Mikey

 

[lacroupade]

I know this will make me sound thick but what happens (mechanically) when I select 4H or 4L. I don't have a rear diff-lock so I assume power goes to all 4 wheels until one losses traction and then that gets all the power. But, that wouldn't explain why my D22 goes just about anywhere, or does the power go 50/50 front/rear so if one wheel slips say on the front both rears will drive. Would that mean there's a center diff that's locked???

Any help would be great thanks

Mikey

As far as I know, its a 50/50 split, front to rear when you engage 4WD, plus allegedly...."The Navara also has a manually operated electric rear differential lock to ensure an equal split of power to the rear wheels under demanding off-road conditions", i.e. when this is selected, even if one rear wheel has no grip and spins the other will continue to provide drive...

 

[zippy656]

T2's have centre locked dif. and LSD rear.

so if you chain a T2 down, 3 wheels will spin and one on the front will be still.

 

[Mikey]

My D22 is a 2003, I can find nothing suggesting there's a rear diff-lock. I do not have a switch for it so can't have one I guess !!!!

 

[zippy656]

jack up onto stands, turn one wheel, with LSD should go same way, with a clocker would go backwards.

 

[Tony]

my d22 hasn't got one but i suspect a D40 may
Tony

 

[Mikey]

Mmm, I think it safe to assume I do not have a rear diff-lock as there is no switch or lever for it and there's no mention in the manual. I guess therefore I'd like to know how the power IS sent to the wheels in 4H or 4L.

 

[Terranosaurus]

None of the above mentioned vehicles has a centre diff at all, therefore it can't be locked but they do behave (traction wise) as though there's a locked one of course as it'sthe same thing. So torque is split equally front to rear, this is why you shouldn't drive them on hard dry surfaces in 4wd.

Mikey check your back axle for a little orange sticker near the oil fill plug - "Use LSD oil" - you may have a model with a rear LSD, some have I beleive.

 

[Tony]

Mine has a rear lsd just changed the oil you notice the difference
Tony

 

[Mikey]

Yes I have LSD, how does that effect 4WD.

So, in 4WD if I have one front wheel off the ground or no traction will that front wheel rotate and the front on the ground not rotate?? Is that the same with the rear? Would therefore, one front and one rear wheel that have no traction just rotate and I go nowhere??

 

[Terranosaurus]

Thats where the LSD comes in.

In say a Landrover (even with the centre dif locked) if you get cross axled so that opposite corner wheels are "in the air" or even just unweighted enough that they will not drive you forward, you get stuck. With an LSD, torque will still be applied to to both of the wheels on that axle so the wheel on the ground will keep you moving forward.

With decent mud tyres and an LSD in the back you can get an awfully long way in 2wd. When I broke a front shaft at Sibbertoft I was still able to continuing playing and drive almost everywhere with just 2wd. In fact I was doing stuff that my mate in his 110 wouldn't attempt as he had to drive it home (like I did) and didn't want to damage it etc Sure I got stuck twice, once in deep claggy mud that no one else attempted all day and once getting up an 3ft high almost vertical climb, a few more mph and I'd have made it but couldn't have a 2nd go as the towbar implanted tself in the ground so I couldn't reverse out to try again.

 

[Mikey]

Good to hear Nissans beating those Land Rovers.

Ok, I get the LSD now. I often wondered why my Nissan just seemed to keep going when others around me (Land Rovers) had to charge at hills I just crawled up. I'm guessing a rear diff lock wouldn't really provide valued improvement then. On my recent trip to Morocco my lonely Nissan managed everything as the 6 Land Rover drivers gave up expecting my to get stuck. The only time I did get stuck was when a 'Landy' dared me to drive into small hilly sand dune area on beach, betting me I would get halfway through. I managed all but the last 15' when all 4 wheels finally lost the fight against gravity and sank. None of the 'Landy' drivers would take it on.

Many thanks to all for help and advise. Thanks Guys.

Mikey