High range 4x4 / Diff lock
Submitted: Sunday, May 08, 2005 at 19:09
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steve21
Hi All.
When traveling say hard dusty road / fire trail when would or would you lock the centre diff? or would you just leave it in constant 4x4. (i have 80 series petrol)
just wondering about trans wind up etc.
in the early stages planning out back NSW trip
thanks steve.
Reply By: dindy - Sunday, May 08, 2005 at 19:24
Sunday, May 08, 2005 at 19:24
steve21
only use diff lock if you have trouble with wheel slip on any given surface. normal running on dirt just leave in constant 4x4 because that is the point of the system to give you good traction in most situations. however don't asume that just because you engage the centre diff lock that you can't get bogged because you can and if you bog the whale good luck getting it out on your own.
dindy
AnswerID:
110334
Follow Up By: Exploder - Sunday, May 08, 2005 at 19:40
Sunday, May 08, 2005 at 19:40
Gday all
First up, I do not have a constant 4*4 so other’s may have different advice.
If travelling on a hard dusty surface (fire trail) wouldn’t worry about it as there is a risk of wind up and it is not really necessary to lock the C/diff.
I only lock it into 4*4 if necessary, Sand, Mud, Steep climb/descent or if use of 4*4 would help stop track damage but only if soft enough to stop wind up from accruing.
FollowupID:
366874
Reply By: F4Phantom - Sunday, May 08, 2005 at 19:38
Sunday, May 08, 2005 at 19:38
The diff may never need to be locked, if the terrain is in anyway not slippery, then you will not need it, if there is not alot of wheel articulation, you also will not need it. Dust - dont bother. Lock it in when there is heaps of slippery or steep and undulating terrain.
AnswerID:
110340
Reply By: Footloose - Sunday, May 08, 2005 at 21:02
Sunday, May 08, 2005 at 21:02
Cruising down a hard dirt track that I'd been down the week before. 2Wd and a car full of passengers yakking away so not paying full attention (bad mistake). Bend had been "clayed" and watered very recently. Skidded off ending up about 1/2 metre from a tree, scary stuff.
I now put the front hubs in on any surface with even a remote possibility. If its wet and dirt or gravel I'll engage 4wd high if necessary.
Better to break the vehicle than break yourself.
AnswerID:
110358
Reply By: traveller2 - Monday, May 09, 2005 at 08:37
Monday, May 09, 2005 at 08:37
I've had cruisers, mostly troopies for over 30 years and always engaged 4wd on loose/dirt surfaces, gives much better traction and braking. In slippery wet conditions I'd occasionally put it in on the tar too.
Now I have a constant 4wd I still lock the centre diff on dirt most of the time especially if it is damp/wet, any sort of slope, unless turning or doing tight manouvres.
You'll never wind the transmission up to cause problems that won't be relieved by reversing a metre or so.
I've seen too many rear and centre diff failures on constant 4wd's over the years due to the drivers not locking the centre diff to spread the load front/rear on loose stuff. Most constant 4wd's have smaller diffs (cruisers are an exception) than part timers on the premise that both diffs are sharing the load which does occur in high traction conditions but can change rapidly on loose stuff and will lead to rear diff failure as it is doing all the work.
AnswerID:
110389
Follow Up By: Toy_Hilux - Monday, May 09, 2005 at 10:29
Monday, May 09, 2005 at 10:29
Hi,
But correct me if I'm wrong, even on my own 80's LC with it being constant 4wd supposedly. It is only constant as it does not have free wheelin hubs that you have to lock in. But it is still only 2WD untill u lock the centre diff which in turn runs the front diff. Even then it is not true 4WD unless diff locks are installed. If you think I am wrong, jack up the vehicle on the rear end and then try to drive off the jacks without the centre diff locked. My LC wont do it without the centre diff locked, and it is supposed to be full time 4WD.
FollowupID:
366927
Follow Up By: BenSpoon - Monday, May 09, 2005 at 14:06
Monday, May 09, 2005 at 14:06
True- with centre diff unlocked, it is effectively a 1-wheel (front or back axle) drive, lock it in and it becomes a 2-wheel (front and back axle) drive. The only thing I'd differ on is "lock the centre diff which in turn runs the front diff" keep in mind the centre diff is still a diff, and drive can be put to EITHER the front or the back. Try jacking up the front axle and driving off- same result as jacking the back.
FollowupID:
366952
Follow Up By: Toy_Hilux - Monday, May 09, 2005 at 15:08
Monday, May 09, 2005 at 15:08
BenSpoon
I'd have to disagree with you on the centre diff. It is in fact a transfer case which houses your High - Low Range as
well as your 4wd status. There are two different transfer cases (not diffs) installed in the 80'series LC. They are a HF2A model and a HF2AV model. The first of which has an electic shift motor activated via a switch which can be used in High range thus giving you 4wd and the other model has a viscous coupling which acts like a limited slip coupling therefore transfering drive to the front diff without the need of locking in on H4, this particular model cant be locked in in high range. My vehicle has the HF2A model transfer case thereby only the rear wheels are driven unless locked in. It is just that instead of having a lever that you manually have to pull into either H2, H4, or L4 where you had to slow down, you can activate 4wd with a push of the button even at 100k. On my wagon the front diff wont drive the vehicle unless I activate the switch to put power to the front diff as
well as the rear. The common mistake that people beleive in is as the vehicle states that it is Full Time 4WD it is in fact not. You just dont have to stop the vehicle to get out and lock in the front hubs. Push a button or pull a lever. L4 automatically locks the transfer case. Non of the latter models have a real problem of wind up that was constant in the older vehicles.
FollowupID:
366965
Follow Up By: BenSpoon - Monday, May 09, 2005 at 17:02
Monday, May 09, 2005 at 17:02
I still am fairly certain on the drive being pushed to both axles... on my 80 I have managed to do front wheel donuts, with no smoking action from the back wheels, indicating drive can go to the front with centre diff unlocked.
Also, dropping the clutch around a gravel corner just flicks stones up from the front wheels, it certainly doesnt make the back end step out or do anything to indicate it being rear wheel drive when unlocked.
Its been the same experiences in both 94 models I have owned.
FollowupID:
366985
Reply By: Member -Dodger - Monday, May 09, 2005 at 10:31
Monday, May 09, 2005 at 10:31
Steve,
You oly need a few bumps that bouce A wheel slightly to relieve any wind up and as with most dirt tracks and gravel roads there are many pot holes and ruts to bounce the wheels.
I tow a 2 tonne van and always run in 4 high when on gravel roads etc this gives better control etc. Oh and
mine is a part time system with a lockrite in the front.
So far 130,000 and no trouble except for the odd
puncture.
AnswerID:
110401
Follow Up By: Member - Duncs - Monday, May 09, 2005 at 11:12
Monday, May 09, 2005 at 11:12
Jsut be a little careful of windup. I had a windup problem on the dirt roads around
Innamincka. Luckily I recognised it in time to prevent any damage.
I used to always hook in teh front diff (Nissan not constant) on dirt but am a little more selective now.
Duncs
FollowupID:
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