Educate Me - The Centre Diff Lock

[Chris078]

One of these days I will get the Perentie in some mud, so I figure I should know about it.

1. What precisely does it do?
2. When should you use it
3. When should you not use it
4. What does it allow you to do
5. How to engage properly? as in, do you need to be stopped like when engaging Hi/Low range, can you be gently rolling, or going flat out?

anything else I should know about it?

As an aside, how much slop is acceptable in the centre diff? at the moment I can roll the front/rear shafts about 1/3 - 1/2 a turn before they stop.

[rangieman]

It aint rocket science:p
It gives you direct drive to the front and back and allows you to 4wd.
Only use where traction could be lost . I use it on dirt roads as well as 4wdriving ;)
No need to stop can be engaged at any speed .
Never use it on bitumen as a t/c rebuild will result:angel:

[DeeJay]

Off Road a Perentie is really only in effect a 1 wheel drive if the centre diff is not engaged & the axle diffs spin (as they are meant to..) because drive will - in some circumstances- only go to the front or rear driveshafts.
With the centre diff engaged, you then have two wheel drive ( one front one rear) as the drive is locked at 50/50 between front & rear shafts. If you fit difflocks then it becomes true 4wd with no diff slippage.
The idea of it is that you get power ( not necessarily traction) at all 4 wheels when the difflock is off, on hard surfaces.
You must engage it if wheel slippage is expected as they are known to burn out the brass shims in them in minutes.
The rotation you are having is normal, actually it's on the side of pretty good !!

[Blknight.aus]

One of these days I will get the Perentie in some mud, so I figure I should know about it.

1. What precisely does it do?
2. When should you use it
3. When should you not use it
4. What does it allow you to do
5. How to engage properly? as in, do you need to be stopped like when engaging Hi/Low range, can you be gently rolling, or going flat out?

anything else I should know about it?

As an aside, how much slop is acceptable in the centre diff? at the moment I can roll the front/rear shafts about 1/3 - 1/2 a turn before they stop.

1. it locks the front ouput shaft of the Tcase to the rear one and bypasses the internal differential action of the differential inside the transfer case. This makes the front and rear axles differential crown wheels turn at the same speed at all times.
2. you should use it whenever there is the probability of wheel slip, I reccomend any time you are not on black top or hard pack road surfaces. If it has gravel or sand you can engage it. if you can see easily discernable wheel tracks and tyre patterns you should engage it. If you are expecting to unload suspension or where you are walking you leave footprints of any kind then you engage it.
3. you do not engage it on hard surfaces when you will not be lifting wheels or you do not expect to break the traction of the wheels.
4. it allows you to lift one wheel off of the ground or to experience 0 traction condition but still maintain effective power to ground through the axle that has both wheels providing tractive effort
5. just back of the accelerator while you actuate the control knob, if it doesnt change state you may need to hold a trailing throttle condition while you steer through a corner or 2, work the steering lock to lock while still maintaining progress and in extreme cases drive in reverse and steer lock to lock under light power.

[Chris078]

Found a nice fire trail at Mt Mee in the D'Aguilar State Forest in Qld yesterday and managed to used the Diff-Lock for the first time.

It's still going so I assume I didn't break anything.
Was fun! :D

[Pedro_The_Swift]

what model transfer case in a Perentie?

[Chris078]

what model transfer case in a Perentie?

Not sure if there is a particular model number.
From the EMEI G100 :>
Manufacturer : Land Rover
Type : Two Speed
Ratios:
High Range: .996.1
Low Range : 3.321:1

[JDNSW]

what model transfer case in a Perentie?

It has the LT95 combined gearbox and transfer case. Most if not all of them, I believe, have a slightly modified version with taper roller bearings on the intermediate shaft.

John

[4runnernomore]

When I got my 110 license code quite a few years ago now the instructions were as soon as you hit the dirt lock the centre diff.