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barney
20th May 2004, 08:08 PM
for the sake of an argument.
now we all know that, despite the ramblings of 4wd monthly about dissappearing centre diff locks in the early series 2 discos, it was always there, only the means to lock it from inside the cabin was removed.
and i think we all realise that landrover realised their mistake and re introduced the means to engage it from inside the cabin in the next lot out of england.
in overlander this month, there is a feature on 2 discos belonging to a couple of guys from the "overlanderforum" who are members of the lroc in syd. they go on to describe the aftermaRKET EQUIPMENT THEY'VE FITTED. one of the guys in the 2000 mod, had a kit fitted by bruce davis to enable him to engage and disengage the CDL from the cabin. then it got a little strange when overlander went on to say about the newer model "the engine and drivetrain remain standard butbeing a later model vehicle there is no centre diff lock in the transfer caseso this couldn't be re-connected"

WHAT THE? do overlander know something that the rest of us don't, have landrover been lying to us? didn't all the 4wd mags recently give a standing ovation when land rover "re-fitted"the centre diff lock. like as though land rover would go to the trouble of designing a trnasfer case with no centre diff lock for one of their top selling models.

of course i could be wrong and land rover have deleted the diff lock?????????????????????????????????????????????? ?????? :?

tempestv8
20th May 2004, 08:41 PM
Hi Barney,

I'll try to explain this from what I know.

When the Disco II was released in late 1999, LR kept the same transfer case that they used on the outgoing Disco I model, i.e. it had a little "nut" on the transfer case which, when twisted to a certain position, engages the internal mechanical links to engage the CDL. But this nut was not attached to anything, so the driver can't engage the CDL. You had to go underneath the vehicle, and use a 10mm open ended spanner to actuate the CDL.

I believe I might have been the very first person in Australia to say, stuff the warranty, I want CDL. So I fitted a Disco I transfer shifter onto my Disco II. The Disco I shifter actuates that nut to engage the CDL.

For a picture of this "nut", have a look here:

http://www.expeditionexchange.com/cdl

All is well and good coz it meant that the Disco II can be fitted out with any suitable mechanism to engage the CDL nut.

Then in a fit of stupidity, Land Rover decided that they wanted to STOP people from fitting CDL engaging mechanisms, so they redesigned the transfer case by *removing* that nut. This was on the late '01 to '02 model Disco IIs. So it wasn't possible at all to fit a linkage to engage the nut coz it wasn't there anymore. Where that nut was supposed to be, the transfer case casting just had a blank. Not even a removable plate. Nothing.

What this means is that the '01 to '02 Disco IIs are totally enuched.

Then when LR realised the issues with loss of CDL were real and could not be solved by the ETC system, they reinstated the original transfer case and built a new lever which could engage the nut.

This happened on the '03 model year DIIs for Australia. In the USA, they still fitted the enuched transfer case. The Yanks didn't get the right transfer case till around '04. Someone may want to correct me on this last bit.

So that is why Simon Lun and Craig Butler were able to engage their centre diff locks - coz they had the right model year Disco II that had the nut.

Hope this makes sense.

Lawrance Lee

chantrys
21st May 2004, 11:20 AM
I can confirm that the '03 Disco has a CDL lever inside the cabin, so obviously they've seen the error of their ways with the early series II.

However, can someone explain to me the benefit (if any) of fitting aftermarket front and rear diff locks in addition to the CDL?

thanks,
Chantry's

Phoenix
21st May 2004, 11:40 AM
on a full time 4x4, drive is differentiated front and rear to stop windup, the CDL locks power 50/50 front/rear, as a part time 4x4 is when 4x4 is engaged (like my series 3).

Diff locks lock the diff in the axle that would normally let the outside wheel travel further than the inside wheel in corners without windup. So if you lock it both wheels travel at the same speed all the time. So corners are nigh on impossible, but if you lift a wheel, both will continue to turn. If an unlocked diff lifts a wheel, then you get no drive from wither wheel. Although the modern traction controll aleviates this problem to some extent.

chantrys
21st May 2004, 12:16 PM
so does adding separate and individual front & rear locks (such as ARB Air lockers) add any advantage over the standard CDL?

Thanks,
Marcus

HSVRangie
21st May 2004, 12:23 PM
YES.
it allows all wheels to have equal driving force at all times.

ETC works but is a PIA. Difflocks work far better in IMHO.

MIchael.

chantrys
21st May 2004, 12:27 PM
so CDL ensure a constant 50/50 split to front and rear but doesn't give equal drive to all 4 wheels.

So if you lift say the front left wheel, you are relying on traction control to transfer drive to the front right wheel, whilst the back ones will continue going as normal??

Thanks,
Marcus

Phoenix
21st May 2004, 12:47 PM
that is right, a diff lock is a mechanical device that ensures bothe weels have equal power.

CDL is front to rear, Diff lock is left to right 50/50 if that helps make sense of it.

tempestv8
21st May 2004, 01:15 PM
One important thing that the Centre Diff Lock does is that it not only distributes the drive equally to the front and rear axles, but *very importantly* it delivers the BRAKING evenly between the front and rear axles.

Now in all vehicles, the front wheels have the bigger, more powerful brakes. And the rears are typically less powerful.

Consider the following situation - you are trying your hardest to crawl up a steep slippery hill but halfway up, your tyres collectively are losing to much traction to keep going. So you stop, with your foot hard on the brakes, the intent being to ease off backwards down that hill to have another go.

Now remembering that the front wheels have the majority of the braking power proportioned to it, and they are now significantly LIGHTER than the rear wheels which have the bulk of the weight of the vehicle on it.

If you do NOT have a CDL engaged, what this means is that when you ease off your brakes a little to allow the vehicle to begin backing up under its own weight from that steep slope, the front wheels remain fully locked and the rear brakes are now tasked with the job of controlling the speed of your descent. This is bad because the front wheels being still full locked, and with little grip or weight on them, means that you've lost any steering ability........ this is BAD! 8O

With the CDL engaged, the front wheels are not allowed to remain locked while the rear wheels are turning. In effect, the braking from the front wheels is transfered thru the engaged CDL to the rear wheels, so in effect, both axles are controlling the descent, not just the rear axle.

So the CDL is very very important for backing down a steep/slippery hill.

Food for thought.

Cheers,

Lawrance

barney
21st May 2004, 04:11 PM
tempest, you obviously read the article, but i understand the principles and the process to lock the CDL, i didn't know they'd blanked it off, but in craigs disco they stated that his was not fitted with a diff lock so the conversion couldn't be done on his. i don't know if they worded it incorrectly or are just plain ignorant.
i only started this to bring attention to the lack of landrover knowledge that some of these "experts" who write for the big 3 have.
i remember a story on 2nd hand vehicles in 4wd monthly. they paid out on the defender because the engine electronics were too hard to fix off road. they failed to mention that of all the jap cars they tested, probably the easiest to get mobile when something breaks, woul be the defender.


i apologise, every now and then i get on my high horse and have a dummy spit.

HSVRangie
21st May 2004, 07:20 PM
THe last of the D11 didnot have the linkages, actuating fork or the sliding gear to lock the centre diff.

All these parts have to be sourced and fitted to the T/case.

Michael.

barney
21st May 2004, 08:18 PM
thanks HSV, i just read an email to that effect from one of our members who, well, let's just say he knows the facts. the reason the guts were taken out was that the centre diff lock caused confusion within the software for the ETC.
the new d111 has an electronically controlled CDL linked to the ETC, as well as tons of other goodies (i've been promised) don't know any more unfortuntely

Slunnie
22nd May 2004, 12:15 PM
Gday Barney,

The interesting thing is that LR don't always get it right either. They said that activating the CDL on the Disco2 would cause "cascade" failures of the electronics if it were activated and run. this is despite the manuals saying that the CDL was left in there for dyno testing.

At a similar time they released the defender with the TD5 and a slightly different ETC system which I think only works across the axle.

barney
22nd May 2004, 05:49 PM
yeah, i know. it's got me stuffed what goes through their heads. while i'm all for utilising available technology to make our life easier, sometimes things just need to be left alone-because they WORK.
god help us in the new fangled disco if it gets a glitch while crossing the simpson or the CSR. i s'pose that's what landrover assist is for. i'm glad i can fix most things on my ute my self. there is a lot of people out there who buy a 4wd for the first time and expect to be able to climb everest in it, who don't know the first principles of how or why a car works. these people are probably given a faulse sense of security by the advertisers of a go anywhere vehicle that will conquer anything, unfortunately these people are not only a danger to themselves but their rescuers aswell.

BTW, welcome to aulro slunnie, i haven't seen you on here before. (this is where i've been hanging out)

Slunnie
22nd May 2004, 06:09 PM
Thanks for the welcome Barney. style_emoticons/<#EMO_DIR#>/biggrin.gif I check in here every now and then.

Interesting point. I was in the desert and the Disco's tranny went into limp mode for some reason. Fortunately it cleared pretty quickly, though it left me scratching my head.

barney
22nd May 2004, 06:12 PM
that would have been a tense moment. nothing worse than something playing up when you need it most

shaunp
23rd May 2004, 06:20 AM
The early series 2 cars had standard transfer boxes ie the spiggot for the diff lock linkage is there but not connected to anything. The later Series 2 cars don't have this nor do they have any of the lock components inside the box. 03/04 cars for the Australian market have the diff lock fitted again however, due to market forces. In most other markets it is an option. You can retro fit the later S2 cars but you have to strip the front of the transfer case including replacing the front houseing and fitting all internal lock components.

barney
23rd May 2004, 04:14 PM
shaunp, i've got it from a pretty god source that most of the components are still there, just the parts that allow the locking mechanism to move are missing. thus rendering the whole thing inoperable unless, as you said, you remove the transfer, strip it down and rebuild it with the missing parts included.

shaunp
23rd May 2004, 05:37 PM
You can do it in the car I reckon. If your box does not have the linkage spigot on top you need the get a new housing as well or machine/ drill old one to take the selector shaft.

Hellspawn
23rd May 2004, 08:24 PM
I like barney's generalisation about people not knowing the how or why their cars work ("Know less"). Now I'm not the greatest mechanic when it comes to fixing vehicles but am sure about the not real need to know. Most "know less" people when something breaks on their vehicle take it to someone who specialises as fixing it yourself done badly is just as dangerous as not fixing it a all.

So I'd becareful about labelling "know less" people who leap in their truck and diappear into the wilds not sure whether they need high four or low range as in the scheme of things, the vehicle can go further than the driver is willing to push it. I'm sure your vehicle could go further than you would be brave enough to go. So to say the vehicles are expected to climb Everest, there is a good chance they could but only certain drivers are talented enough to push their vehicle to the extremes of it's capabilities.

barney
24th May 2004, 06:44 PM
hellspawn,
i get the impression you may have missed my point. i was pointing out that too many people put too much trust in technology. sure, it's great when it's working but not much good to you if it claggs out in the middle of nowhere.
i was just informed today of 2 of our lroc club members who are doing a trip up cape york that have come to grief on the wenlock.
water was apparently 1m deep and both td5's got stuck in the soft sand, the water came in and drowned the computers. they have been stuck up there for 5 days now with no help in sight. landrover assist wont help because they have got themselves into it by exceeding the fording depth.
now having mechanical know-how may not be any good to these guys at the moment, but by the same token, they should've been prepared for this type of catastrophic failure, by either taking steps to waterproof the computer enclosure or maybe taking a spare (cost inhibitive).
if the computer is just wet, there is achance that when it is completely dry, it may get them home. but more likely the water has sent power to spots it shouldn't be and done irrepairable damage.
and yes, people servicing their own cars without the proper know-how can be very dangerous, but then again, so can trusting a well known, land rover "specialist" to do your repairs and then finding out after you've paid for it and gone back to pick it up to find that they have snapped the brake adjuster on the rear drums while adsjusting them (not requested as part of service, only engine tune up )leaving me with nearly no pedal and adjusting the idle too low so that to keep the engine running, one must keep the go pedal down.
this became very awkward getting the vehicle home, pumping the brakes to stop while keeping the revs up so as not to stall. the company in question would not pay for the replacement backplate for my rear brakes and it took me a month of fiddling to get the thing running right again.
as a footnote to this, when changing my gear, transfer and diff oils 20000k's later, i found that they put the wrong oil in my transfer.

this is why i service my vehicle my self and i'm confident that in the event of a breakdown anywhere, that providing nothing is totally knackered, i'd have a good chance of getting mobile again. but in a remote area, you can't rely on your own skill and should always have communication backup (hf or satphone) just in case.

Hellspawn
25th May 2004, 10:17 AM
Nope, didn't miss you're point about technology but what you go on to say is a dig at people who really don't worry about whether they have (including me) traction control, freewheeling hubs or central diff lock engine management or some other optional accessory will allow the vehicle to be parked on a wall in the event of no gound parking spaces. It is both a blessing and a concern that we live in such a world full of automation and computers but I'd guess that if we didn't support it then we'd probably not buy it.
As for the troop at the Cape, I suppose there could be worse places to be than there. You're right, they should have prepared for something like that, same as driving in the scrub without a spare tyre or tube. In hindsight they could have in water proofing the ECU mounted in on the roof before they left or precrossing wrapped it in cling wrap then put it a plastic bag tying the end around the loom. My figuring is stick to the basics, points ignition, carby and standard size wheels. Most can be found or at least fixed which is better than sitting for days with a multimeter of which most of those parts aren't repairable anyhow.
Sounds like you had a bit of bad luck with that particular dealer. I could say the same for spare parts outlets but haven't yet resorted to manufacturing my own brake shoes or oil filters.
Quite right, no shame in asking for help than wander further into trouble on half done mechanicals. Yet that's just another funny thing about people who fix their own as opposed to take it to someone types, the later will normally be the first to stick their hand up for help. Fix their owns from whom I've met in wanderings generally dig their heels in about some other touching their car, whether it be cost or embarrassment or as was your case with the dealer just bad service I could never get it out of them. Weird really.

barney
25th May 2004, 12:48 PM
no, again , hellspawn. quite the opposite. i'm a carby/points man myself, i'd much prefer a difflock than traction control etc, etc.
im' more concerned about the people that go bush, unprepared, blindly trusting the technology that they've bought or been promised by the dealer with out any preparation or chance of saving themselves.
that's it ......subject closed. i thuoght my point was pretty clear in the first place.. explaining a comment 3 times is too much.