ABS retro fit

[Olsmokey]

Anybody know if this is possible?

The reason I ask is I have been reading as much as I can about it, and much of the comment is just plain missleading, ie someone claimed you would need to swap complete axles, obviously they have no clue of the difference between an ABS and a standard axle.

Why do I want ABS? The simple answer is that a full locker does not appeal for technical reasons, it seems ABS and ashcroft ATB diffs is simply a far more elegant solution for pretty much all eccept maybe the winch challenge boys.

Also after doing a little looking on fleabay defender ABS parts are pretty scarce and expensive, however disco 2 ABS parts are plentyful and cheap, so is there anyone with an informed opinion about fitting a defender TD5 with either disco or defender parts to make a fully working system?

[Guest]

The ABS system is separate so you should be able to retrofit, the question was asked a while ago and I did list the bits you needed, but as the search function is great I can't find it!!

You will need to re-plumb the whole system as each pot needs an independent fluid line

Rear hubs need to be ABS ones with the holes in them and then the ABS ring in the rears discs

You would then need sensors for each wheel

Front wheels need to have abs swivels where the sensor drops in the top

You would then need the abs block and the abs ecu and of course the loom job done!!

Jason

[101sean]

Not really feasible unless you are really keen. I have an ABS equipped Defender.

Rear axles sensor reads off a serrated plate behind the brake disc and is mounted in the axle end, also requires a different stub axle with a cut out to clear the sensor. I'm not sure if the sensor mounting is present on a standard axle.

Front sensor is mounted in a hollow top swivel pin and reads of the serrated edge of the CV joint so you'd need to change both

Servo and master cylinders are different to standard.

ABS modulator is the same as the D2 but is wired differently, I don't think the pin outs are the same and uses a different ECU to D2.

[=jon=]

it seems ABS and ashcroft ATB diffs is simply a far more elegant solution for pretty much all eccept maybe the winch challenge boys.

I think you mean traction control, not ABS... ABS will un-apply the brake if the wheel locks, traction control will apply the brake to stop the opposite wheel spinning... Same sensors, different (much later and therefore more rare?) ECU, and possibly a different pump too.... A fiddle brake setup would work out way cheaper and a lot easier to do... (or left foot brake and use more accelerator!)

Also - why would you need the ATB diff with the TC? Unless I'm missing something major they will both do the same function:

ATBs only operate when there's 'load' on both wheels. So with one wheel in the air it'll act 'open', the unloaded wheel will spin and you'll get nowhere.

The TC will use the brakes to lock the opposing wheel, so the loaded wheel gets all the power. If one wheel is locked with the brake, all the power will go through the other wheel, open diff or ATB... I admit, you'll probably get further with an ATB than a plain open diff before the TC kicks in though...

Or am I misunderstanding what you are asking?

[sean f]

I have been re engining a P38 and in doing so totally re wired it, I had concerns over the ABS as I wanted to keep it if at all possible. Turned out to be quite simple, it took a bit of studying the wiring diagrams but I got there in the end, a few wires weren't needed as the ABS module sends a speed signal to the BECM and signals to the cruise control etc, I simple cut them off, even kept the ABS warning light on the dash although this now flashes until the vehicle gets to 5mph then stops (warning light is supposed to stay on till 5mph but is normally solid not flashing).

The vehicle this was on had traction control (not all P38's did) so I assume this will still be working although as yet I haven't played enough to check.

Lots of scrap P38's about so they might be a better source of bits although I expect you would need to transplant the entire system, the brake valve block is not exactly small and you would need to fit the electric brake pressure pump (I assume these would be needed on any traction control system in some form).

[rekab69]

I converted a drum axle to disc brake for my 110 defender which has ABS \ TC you will need to drill two 21mm (i think they are) holes for the ABS sensors quite straight forward.. so thats the rear axle sorted..

Good luck with the rest,

db.

[Escape]

Olsmokey,

I had a Defender TD5 with ABS, and took it all out when I fitted ARBs and relocated the engine ECU. I couldn't find a good spot for the ABS ECU and as the car was only used offroad and the lockers negated the need for TC, it was easier to just take everything out.

So if you're serious about fitting ABS, I have most of the parts: 4 sensors, ECU (including connector, wiring loom not complete), modulator, CVs with ABS ring and probably even the swivels and rear hubs to fit the sensors. It would still be a lot of work, replumbing the brake lines and wiring sensors and ECU, but feasable.

Send me a pm if you're interested, some friends are going over to UK in a few weeks, I could ask them to take the parts with them.

Greetz,

Filip

[rick]

I think you mean traction control, not ABS... ABS will un-apply the brake if the wheel locks, traction control will apply the brake to stop the opposite wheel spinning... Same sensors, different (much later and therefore more rare?) ECU, and possibly a different pump too.... A fiddle brake setup would work out way cheaper and a lot easier to do... (or left foot brake and use more accelerator!)

Also - why would you need the ATB diff with the TC? Unless I'm missing something major they will both do the same function:

ATBs only operate when there's 'load' on both wheels. So with one wheel in the air it'll act 'open', the unloaded wheel will spin and you'll get nowhere.

The TC will use the brakes to lock the opposing wheel, so the loaded wheel gets all the power. If one wheel is locked with the brake, all the power will go through the other wheel, open diff or ATB... I admit, you'll probably get further with an ATB than a plain open diff before the TC kicks in though...

Or am I misunderstanding what you are asking?

A torque biasing diff with TC is much more effective than TC alone, or at least the early iterations of Land Rover's TC, according to those that have done it

[=jon=]

A torque biasing diff with TC is much more effective than TC alone, or at least the early iterations of Land Rover's TC, according to those that have done it

I drove a '11 Defender round one of LRs tracks, and the TC was a bit clunky, but effective - you could get it to go with diagonally opposing wheels off the ground - however to get the TC to kick in you needed to give it a lot of welly - then you'd get a lot of mechanical clunking and it would move off... On gentle throttles it would quite happily spin the lifted wheels...

[Guest]

Resurrecting an old thread but there is a step by step guide in this Months LRM on how to do this, and what is needed.

If anyone needs a copy I can scan and email it to you.

Jason

[simonr]

I did wonder, reading this thread if it would be workable to just drill 30 o so holes in each of your disks and have a sensor external to the hub?

I drilled a load of holes in a certain disk handbrake for a speedo pickup - which worked really well!

The TC on D2's seemed to work very well - certainly a lot better than the Defender version!

Si

[Captainbeaky]

Resurrecting an old thread but there is a step by step guide in this Months LRM on how to do this, and what is needed.

If anyone needs a copy I can scan and email it to you.

Jason

Yes please mate.

I'm just about to buy a 50th, and would like to fit ABS.

Thanks,

Mike

[Maverik]

Bit of a thread revival, but has anyone successfully completed this? Anyone by any chance have a copy of that article?

Mav

[Green200tdi]

My 1986 90 had a H reg Range Rover classic rear axle with disc brakes and ABS sensors I remember removing them so guess yes you need either abs axle or at least the ends 

[Maverik]

So I've just acquired an ABS Discovery 1 (300tdi) with all the bits, doesn't work by the look of it, but! I've got a notion to try transplant it over to a 90.

[Snagger]

Good luck.  While the ABS system on my late RRC was brilliant, the same can't be said for the system on my 2009 90XS - it still locked up on frost block paving, unlike the RRC, and the pedal would sometimes vibrate and make a strange noise, even though the system was all in good order.  I have heard numerous other people say that pedal vibration is a common characteristic, but it's unsettling.  I had been considering fitting that system to my 109, having been so impressed with the RRC''s brakes, but once I had driven with it, I immediately abandoned the idea - the 109 had far better skid resistance with standard Discovery 1 brakes and BFG ATKOs on those frost bricks than the 90 with Michellin road tyres and its ABS.  I think you're onto a fool's errand, unless you go for the Range Rover system.

What would be nice is to have four way ETC, which would trigger ATBs superbly.  ETC works to a point, but saps so much power that it's a very poor substitute for locking diffs.  ATBs are seemingly superb unless one wheel looses all grip, and so the ETC would work wonders, triggering the ATB and then deactivating.  It's a shame the RRC system only has ETC on the rear axle.  I don't know if the D2/late Defender system has 2 or 4 channel ETC.

[Escape]

D2 and late Defender (TD5 on) have 4 channel ETC, as does the P38 from '99 on. It works great but as said does sap some power.

[Snagger]

All the experienced desert drivers here remove the ABS/ETC fuses from their vehicles before going onto the sand  for that very reason, no matter the vehicle used (typically Jeeps, FJ Cruisers, Land Cruisers and Patrols).  ETC seems good for shallow mud, snow or ice, but a liability in soft sand.

Any idea if the later P38 ECU would work with the late RRC system to give four channel ETC?  I’d be quite content with that as it’d only be for wintry conditions, not even laning.

[Gazzar]

Watching this thread with great interest. A switchable driver aids system makes a lot of sense, if used to augment the mechanical stuff.

[FridgeFreezer]

Don't modern LR products have a specific sand setting? Can't believe that's useless on sand, although I can well imagine less well developed systems would be.

As ever, understanding how the system works & the limitations that brings is helpful, but no-one's got time for thinking

[elbekko]

4 hours ago, Snagger said:

Any idea if the later P38 ECU would work with the late RRC system to give four channel ETC?  I’d be quite content with that as it’d only be for wintry conditions, not even laning.

Nope, the valve block is different inside.

[Maverik]

The later Wabco ABS ECU's have a Traction control built into them apparently - had an idea of trying to get one of those to talk to the older 300tdi pump/sensors. All being Wabco kit hopefully they will have some compatibility.

I've driven our team Tdci's through most conditions your average Scottish year can throw out and never gotten stuck, for the "design" capabilities of a Defender, I feel the Traction control/ABS function is a pretty valuable function versus a vehicle without the function.

[Snagger]

3 hours ago, FridgeFreezer said:

Don't modern LR products have a specific sand setting? Can't believe that's useless on sand, although I can well imagine less well developed systems would be.

As ever, understanding how the system works & the limitations that brings is helpful, but no-one's got time for thinking

I’m deferring to the wealth f experience that the desert drivers have here.  It is a universal opinion that ETC saps too much power in the sand.  It surprised me, but I have no deep sand driving experience while most members in that club have been doing it for well over twenty years.  That’s a considerable amount of expertise to argue against, John.  Of course, the biggest aid to sand driving would be the right tyres.  We know just how flexible modern LRs are in that department...

[Snagger]

1 hour ago, Maverik said:

The later Wabco ABS ECU's have a Traction control built into them apparently - had an idea of trying to get one of those to talk to the older 300tdi pump/sensors. All being Wabco kit hopefully they will have some compatibility.

I've driven our team Tdci's through most conditions your average Scottish year can throw out and never gotten stuck, for the "design" capabilities of a Defender, I feel the Traction control/ABS function is a pretty valuable function versus a vehicle without the function.

That’s what I’d hoped - the Wabco system in the soft dash only has rear ETC, which is a pity.  For what I do with that car, ETC would suffice, but it has struggled with the front in snow.  It’s a pity that the valve block is incompatible with the P38 ECU, Elbekko.  Any idea if it’s plausible to fit the P38 valve block to a Classic?  I’d imagine the sensors could be a problem, though brake lines should be OK.

[FridgeFreezer]

1 hour ago, Snagger said:

I’m deferring to the wealth f experience that the desert drivers have here.  It is a universal opinion that ETC saps too much power in the sand.

I can believe that for many systems, including the older ones prior to Terrain Response where it didn't know what surface you were on and therefore couldn't make smart choices about how to behave, and I can well believe that once everyone "knows" that ETC doesn't work in sand & pulls the fuse, that's what they'll do forever no matter the vehicle.

It may well be that just pulling the fuse is as good as anything anyway, especially if the local spec stuff has factory lockers (which some did).

Interestingly, Tom Sheppard in his more recent book was trucking about the desert in a G-Wagen which has as much articulation as a shopping trolley but does have a rear locker, and if anyone knows sand driving it's him.