ARB Front Locker Available.....soonish

[FenianEel]

Hey Folks,

Just a heads up, there's an impending release of front Air Locker for the the D3/D4.
Part number RD217
For Landrover Discovery 3 & 4, 29 Spline Front

They can be back ordered from your local ARB now.

However.....there's no specified date at the minute, when they will be off production and ready to be fitted. :p

At least it's confirmed they're on the way, and another solution for Lockers for D3&4's is out there. ;)

[101RRS]

Hmm I understand that the RRS/D3 rarely has its cdl locked with the vehicle mainly 2wd - rear wheel drive until the various loads etc indicate to the computer to progressively lock the cdl. ( I think it is locked in Rock Crawl low range).

A rear locker would have been better but I suppose ARB think that most people interested in a locker will have the OEM rear locker fitted so there is more of a market for a front locker rather than a rear one.

Garry

[gghaggis]

There is absolutely no need for a front locker on a D3 or D4. Rock-Crawl can lock up the front far more effectively, as it will allow a variable delta between the front spins when turning, and won't contribute to shock-load.

One assumes ARB will also source the HD axles and CV joints that will inevitably be required? They'd have been better off producing a rear locker for those that didn't spec one at build time - at least LR provide heavier rear components that could be retrofitted with it.

Cheers,

Gordon

[BigJon]

Hmm I understand that the RRS/D3 rarely has its cdl locked with the vehicle mainly 2wd - rear wheel drive until the various loads etc indicate to the computer to progressively lock the cdl.

Garry

Having a CDL unlocked doesn't make for 2wd operation any more than an open rear diff in a 2wd car makes it one wheel drive.

[101RRS]

Having a CDL unlocked doesn't make for 2wd operation any more than an open rear diff in a 2wd car makes it one wheel drive.

In normal operation most drive goes through the rear axle - hence its larger housing size and double the oil capacity - 1.1 litres in the rear diff 600ml in the front. In rough going (not in rock crawl low range) drive is transferred between the front and rear via the Traction Control system like an early D2 and when the computer senses this is not working it then locks up the CDL. This process may happen almost immediately though.

Garry

[Celtoid]

If they drive mainly from the rear, why do they wear front tyres first? :confused:

[TerryO]

If they drive mainly from the rear, why do they wear front tyres first? :confused:

Might have something to do with that dirty great big engine parked just above them and the fact that the front tyres get all of the steering strain and most of the braking force through them...;)

Re lockers. Considering its near impossible to find a D4 with an e-diff I would have thought a rear locker would be a much better idea.

cheers,
Terry

[isuzurover]

...

One assumes ARB will also source the HD axles and CV joints that will inevitably be required?

...

As they do for all the other front lockers they sell?

[gghaggis]

As they do for all the other front lockers they sell?
No they don't, but for most other brands, such things are available. For the D3 or D4, they're available for the rear, not the front, AFAIK. The rear would have been a better option.

Cheers,

Gordon

[Celtoid]

Might have something to do with that dirty great big engine parked just above them and the fact that the front tyres get all of the steering strain and most of the braking force through them...;)

Re lockers. Considering its near impossible to find a D4 with an e-diff I would have thought a rear locker would be a much better idea.

cheers,
Terry


Oh, so that's why it's so hard to jack the bloody thing at the front?... ;-)

[Owen]

I will be in for one, Toolangi mud had my front brakes smoking with the tc working hard, the rear elocker worked a treat though. Would also be good in soft sand to save the brakes.

Price will be interesting .... As will the comparison out of the USA....

[~Rich~]

There is absolutely no need for a front locker on a D3 or D4. Rock-Crawl can lock up the front far more effectively, as it will allow a variable delta between the front spins when turning, and won't contribute to shock-load.

One assumes ARB will also source the HD axles and CV joints that will inevitably be required? They'd have been better off producing a rear locker for those that didn't spec one at build time - at least LR provide heavier rear components that could be retrofitted with it.

Cheers,

Gordon

Yep exactly Gordon, seems a bit silly doing the front one.
When climbing steep rocky hills it's the rear one that does all the work.
Too easy to break CV's & axles in the front is you push it too hard with a locker on. Not to say that steering is also impaired with the use of a front locker.

[101RRS]

While the housings and oil capacity between the front and rears are different, I assume the diff ratios are the same (noting many AWD cars have slightly different ratios between front and rear) and the actual diffs are the same - if so I wonder if this locker would actually fit in the rear.

I guess that time will tell.

Garry

[chuck]

We should as a group contact ARB regarding rear lockers.

If we could give them 100+ orders that might give them the impetus to go in to design, development & manufacture.

Who's up for 1??

I am.

Cheers

Chuck

[Disco4SE]

I'm tipping that your warranty would be thrown out the window should you have the ARB diff lock fitted.......

Cheers, Craig

[connock]

Oh, so that's why it's so hard to jack the bloody thing at the front?... ;-)

Try putting your jack in the small hole in the front wishbone, wind the jack 2 or 3 turns the car self levels and presto the wheel is off the ground.:)

connock

[Celtoid]

Try putting your jack in the small hole in the front wishbone, wind the jack 2 or 3 turns the car self levels and presto the wheel is off the ground.:)

connock

Thanks mate...never heard of that or tried it...is it safe with the Sus still active?

Basically I was taking the Mick out of Terry....:D

[TerryO]

Basically I was taking the Mick out of Terry....:D

Really! How unusual ...;)

cheers,
Terry

[Celtoid]

Really! How unusual ...;)

cheers,
Terry

:D

Cheers,

Kev.

[isuzurover]

...
When climbing steep rocky hills it's the rear one that does all the work.
...

I used to think that, until I got a front locker...



No they don't, but for most other brands, such things are available. ...

Now maybe, but how many vehicles had upgraded axles available when ARB first released lockers for that vehicle...? My guess would be 0.

[oldsalt]

We should as a group contact ARB regarding rear lockers.

If we could give them 100+ orders that might give them the impetus to go in to design, development & manufacture.

Who's up for 1??

I am.

Cheers

Chuck

Good idea Chuck ... put me down for one :)

[minibloodhound]

Seeing as how the RRS and the Disco is basically the same underneath...would that mean the diff lock would fit say a 2006 sport? I know someone who is trying to get more traction to keep up with my D4!:p

[DoctorJ]

Just got back from a trip up in the high country showing a brother from Brissy a few sights to a message from a mate at ARB about a new front diff lock, couldn't believe it! For those that are seeing it negatively I see it as a real positive. We constantly whine about ARB not providing enough accessories for the D3/D4 and yet when they produce what I believe to be a world first the negative comments come out. Would I prefer to have a rear diff lock? Bloody oath. Would I prefer to have a diff lock or not have a diff lock? Well I think it's obvious. I think we need to give ARB the credit they deserve in assisting us D3/D4 owners who take our fourbys out a better vehicle again.

Cheers
Julian

[discotwinturbo]

The thing is Julian, there are some people on this forum who do know what they are talking about.
And then again ARB do have engineers that know the stuff, and you would think that they have tested the front diff in real world on the D4 and 3.
I don't need one, but waiting to see those that have them fitted if they work with the terrain response or will cause damage.
Time will tell.
But research would suggest that maybe there are plenty of D4 and 3's out there that don't have a rear diff. A rear diff majority of the time will be far more useful than a front locker. Fitting a front locker to a gu patrol.....those that ever did that, wished that had put it on the rear. The rear LSD is great, but not as good as a locker. I know this from experience and from my fathers business that specialist in offroad accessories.
Brett.....

[isuzurover]

The thing is Julian, there are some people on this forum who do know what they are talking about.
And then again ARB do have engineers that know the stuff, and you would think that they have tested the front diff in real world on the D4 and 3.
I don't need one, but waiting to see those that have them fitted if they work with the terrain response or will cause damage.
Time will tell.
But research would suggest that maybe there are plenty of D4 and 3's out there that don't have a rear diff. A rear diff majority of the time will be far more useful than a front locker. Fitting a front locker to a gu patrol.....those that ever did that, wished that had put it on the rear. The rear LSD is great, but not as good as a locker. I know this from experience and from my fathers business that specialist in offroad accessories.
Brett.....

I suspect ARB went for the front locker first - both due to the e-diff, but also due to the fact that it was easier - I have posted comments before by ARB R&D engineers that it was going to be a lot of work and expense to design a locker for the rear.

I have seen plenty of patrols in action on the east coast that went amazingly well offroad with a front locker and a rear LSD.

[discotwinturbo]

"I have seen plenty of patrols in action on the east coast that went amazingly well offroad with a front locker and a rear LSD"

Full articulation with wheel of the ground and the LSD is useless. We performed tests with clients time and time again to prove to them having a rear locker was superior than LSD and front locker....it always went further when full articulation was part of the course. Most situations are on a climb, and the front unloading saw the locker working, but no forward movement....LSD did nothing. Same spots with rear locker made it comfortably. Then double diff locked is better again.

Customers always chose the rear locker then.

Rear locker being more difficult to develop makes sense.

Brett....

[isuzurover]

"I have seen plenty of patrols in action on the east coast that went amazingly well offroad with a front locker and a rear LSD"

Full articulation with wheel of the ground and the LSD is useless. We performed tests with clients time and time again to prove to them having a rear locker was superior than LSD and front locker....it always went further when full articulation was part of the course. Most situations are on a climb, and the front unloading saw the locker working, but no forward movement....LSD did nothing. Same spots with rear locker made it comfortably. Then double diff locked is better again.

Customers always chose the rear locker then.

Rear locker being more difficult to develop makes sense.

Brett....


My observations are completely opposite. I have seen (and have video somewhere) of patrols with only a front locker climbing as well as a twin locked 110 or RR/Disco. The LSDs may have been modified, however the owners of course always complained they didn't work...

Also - one of the 4x4 mags did a front vs rear locker test, and found that front-only (+LSD?) was better than rear only.


EDIT:
4wheelingOZ Products Page (http://winter2005.4wheelingoz.com/wi05%20LOCKER%20TEST.htm)

[Disco4SE]

Went off road with a mate last weekend.
He has a new Patrol with front diff lock. I have the e-diff.
Had to pull him out 3 times, wheras I didnt get bogged at all.

Having said this, the main issues here were him being slung up due to the deep muddy wheel ruts. I used the Llams to raise it up enough to clear the underside of mine.

Cheers, Craig

[connock]

When I had my defender I had F and R air lockers. The combinations were great C locked with just front or just back or all three etc. I found that just the front locker in the sand was the best and occasionly with the C locked as well. as for climbing up rocks all three on and would turn off F for sharp cornering ( unless I was poping wheels in the air ) As for the D3 needing a F locker, The TC and E Dif work unbelievably well and I would not go this way. It would be interesting the watch a few in action though.:)

connock

[Graeme]

Hmm I understand that the RRS/D3 rarely has its cdl locked with the vehicle mainly 2wd - rear wheel drive until the various loads etc indicate to the computer to progressively lock the cdl.
I thought someone else may have picked-up on this but I don't agree that the vehicles are basically 2WD. The centre diff drives both front and rear tailshafts almost identically in normal operation, with the rear diff working harder when the front wheels start to slip due to weight transfer to the rear wheels giving them more traction and the front wheels less traction. The centre diff doesn't have to be partialy locked to drive both front and rear diffs equally if traction on all 4 wheels is identical. There is no front or rear biasing mechanism in the centre diff, only front to rear slip management.

[101RRS]

The centre diff doesn't have to be partialy locked to drive both front and rear diffs equally if traction on all 4 wheels is identical.

I agree when the road surface has the same level of traction as on the bitumen but in most moderate offroad situations the level of traction is different with the rear taking most of the drive.

Garry

[FenianEel]

Anyway....they're able to be ordered & should be available February.

[roamer]

Anyway....they're able to be ordered & should be available February.

And the price is ???????

[theresanothersteve]

If they drive mainly from the rear, why do they wear front tyres first? :confused: Steering and braking places a greater load than normal drive. The front wheels also take a bit of the load during acceleration in an AWD vehicle.

We live in the hills, where steering and braking happen a lot. My wife worked for a government department, based locally, and they struggled to get more than 25K from the front wheels in the front drive (and underpowered) fleet when we expected to get 60K from tyres.

Interestingly, contrary to popular belief, tyre wear is accel;erated (no pun intended) when the roads are wet. Rememeber a motorcycle record attemp (how far one person can ride in 24 hours) when tyre wear increased while speed decreased when it started raining mid attempt. The tyre engineer felt it was because water is a lubricant used when cutting rubber, so it was easier for the road to slice the rubber at a quicker rate.