Fitting coiler axles to leaf sprung 88"

[Duncan]

Hi all, I feel the time has come to finally get some disc brakes under my Lightweight, I'm not interested in the 11" conversion.

I was contemplating fitting Toyota axles with leccy lockers for various reasons(13% higher gearing-just right, High up rear tracking rod to avoid the springs)but the price is just ridiculous for a pair.

I will have my hands on a set of Disco axles off a breaker which I assume I can fit series Diffs too to keep the gearing the same(Don't want the 33% increase as I do tow trailers, and steep Devon hills) I assume this is fine as you can fit disco diffs to series axles, don't hear of the reverse haha

Only real problem to overcome is the front Axle tracking rod wants to be exactly where the Leaf springs are!

My Lightweight has extended Shackles which most people add to help twist the springs down, but at the front I have welded on Rocky Mountain twister schackles so flattens the spring back out so no help there.

3 approaches commonly known(Assuming the axles are fitted with the camber there designed to run)

-move the axles away from the springs to achieve the clearance

NO WAY! not lowering the front back down finally have her sitting level.

-Make spacers for the track rod so theres 2 inch spacers between the track rod ball and the steering arm

Sounds pretty dodgy to me, next please

-Fit axles with the track rod at the front, do any disced axles like this exist(if santana can you get hold of them?

Best Idea i'v heard is to get a LHD disc'ed axle so the O/S wheel has the front steering arm and fit the whole O/S assembly to a normal RHD axle so you have both wheels with steering arms, on the N/S steering arm you would then weld a cut off steering arm in the right place that would fit a track rod to that would go to the new O/S steering arm.

The weld would have to be professionally done if even possible(Cast steel?) obviously the Ackerman angles would be off but would you really notice, it's how the series axles are right!?

Any ideas much appreciated thanks

[Landy-Novice]

http://forums.lr4x4.com/index.php?showtopic=32840

http://forum.difflock.com/viewtopic.php?t=59771&sid=1d59524fd566e95b72b4424077534c0d

http://www.expeditionportal.com/forum/threads/26166-Range-Rover-axles-on-Series-IIa

i have read the third link as im to tired, but it looked good.

[ToyRoverlander]

You could fit 40 or 60series cruiser axles, the ones without the factory lockers have a way more attractive pricetag, lockers can always be added later. Gives you a disc braked front, 4.1 diffs, stronger axles and the steering has the same setup as a Series LR.

Or use Disco/RR axles. Your Series diffs slide right in.

And do this, fit a lhd swivelhousing so you have both arms in front of the axle and make the steering like this guy did.

This is what he has to say about it:

I used 3.5" lift front leafs from a YJ to keep it SUA on a set of Discovery axles, I had to move the front mounts forward a bit and the rears back a few inches. I think they're about 6" longer than stock and were $60 for each pack. I used a RHD D1 steering knuckle on the right side and bored the arms for 3/4" heims to get a "high steer". 6" shackles and kept the stock shocks and mounting locations. It rides much better than stock and steering radius is now very tight.

[missingsid]

Thanks for the pics as this is exactly what I was thinking of doing either by using a LHD hub or just put them on the other way around!

Marc.

[Snagger]

Have a look on my blog - I have recently fitted coiler axles to my 109 and it's all documented and photographed.

[Duncan]

Snagger I'm probably being blind here but I can only see you fitting your already prepared axles all shiney are there pics of the cutting and welding and parts sourced from etc?

Thanks for those pics ToyRoverlander that's just perfectly what I'm thinking right now, With any chance the disco axles I'm getting soon being a 92 i think will accept series diffs and the 90 single line callipers which i think the 92's should!?

Is that guys saying he fitted longer front springs like you Just because he wanted to or to help with fitting the axles?

[ToyRoverlander]

Is that guys saying he fitted longer front springs like you Just because he wanted to or to help with fitting the axles?

He wanted it as it rides so much better than the short stock front springs, and they are lift springs, so he probably needed the extra height to match the rear end.

[Snagger]

Snagger I'm probably being blind here but I can only see you fitting your already prepared axles all shiney are there pics of the cutting and welding and parts sourced from etc?

Thanks for those pics ToyRoverlander that's just perfectly what I'm thinking right now, With any chance the disco axles I'm getting soon being a 92 i think will accept series diffs and the 90 single line callipers which i think the 92's should!?

Is that guys saying he fitted longer front springs like you Just because he wanted to or to help with fitting the axles?

Go to the axles section and look through the various posts. There are plenty of them, not just on that front page - you need to click the "older posts" icon to go back to the previous ones showing the axle conversions.

Do not try to use a track rod in front of the axle by using LHD and RHD near-side swivel housings like that American vehicle ToyRoverlander showed - the steering arms on the swivels will be in the wrong place relative to the swivel pin axis and will reverse the Ackerman angles, so the wheel inside the turn will pivot less than the wheel on the outside, leading to tyre scrubbing, component wear and vehicle instability. Frankly, I think it could be dangerous. There is just no need for it anyway - you have to make the saddles taller because of the diff position; my right hand saddle is very slim over the diff housing, protruding no more than a couple of mm, and making the saddles any shallower would have required notching the diff housing for the spring to sit into. I put the saddle heights on another similar thread not very long ago.

I regained the front ride height lost by the taller saddles by adding a third leaf to my fairly flat parabolics. It seems to work well and has stiffened the front end up nicely on my fairly heavy vehicle. ToyRoverlander has modified his own front suspension in a similar way to that US vehicle with extended dumbirons and rear springs. It gives a greatly increased amount of articulation as well as regaining the lost height, and because the height gain is over a greater length than my recambered standard length springs, it'll give a less curved spring profile which helps a lot with spring rate and compliance. It's a nice mod, but not necessary - using long rear shackles and recalculating the angle at which to attach the saddles tot he axle to allow for the different spring axis angle will be sufficient.

[Duncan]

How important are the Ackerman angles though? at the front is how series axles run, are they designed differently or something? My front tyres do wear down lots faster than the rear though haha

[ToyRoverlander]

.....are they designed differently or something? My front tyres do wear down lots faster than the rear though haha

They are. Steering arms point out more, so when drawing a line through the TRE hole and the swivel pin you'd end up somewhere near the middle of the rear axle. Or at least somewhere close. It's not totally accurate as the 90/110/130 all use the same front axle with the same ackerman angle even though the wheelsbase varies a lot!

I've read posts like Nick's above, advising against it. And I've read plenty of posts of people who've actually done it and report that handling isn't actually any worse, or sometimes even better than stock. IIRC racecars actually have reversed ackerman to improve certain cornering behaviour.

[Snagger]

Ackerman angles only need to be precise for high speed vehicles. For Land Rovers, they can be fairly inaccurate, but they need to be "in the ball park" for handling, grip and mechanical reasons. LR compromise by having one set of swivel housings and arms for four different wheel bases - the 90, 100" RRC and Disco, 110 and 130, and that's just to save costs on production and parts logistics. Tyre size and wheel offsets would also affect ideal Ackerman angle ratios, but there is no possible adjustment for this on our vehicles with standard parts.

Racing cars corner at speeds which lift or at least remove almost all the weight from the inside wheel, so it only scrubs lightly. Land Rovers don't corner well at such speeds... It'll also force a wheel to lose traction cornering off road. If it helped in any handling or mechanical way to reverse Ackerman angles, Land Rover and other manufacturers would produce the cars that way, but none do. It might have applications in racing, but I can't imagine why because you are still forcing a skid. Rally and F1 cars certainly have normal geometry, so any racers that use this might have it to deal with other anomalies like NASCAR racers, which use different diameter wheels on each side because they use oval circuits and all turns are in the same direction with few, if any, straights.

It really is a bad idea on a Land Rover, and as I said, is of no benefit - it'll cost you a new swivel housing and require custom steering rods with a T-joint to connect the drag link to the track rod, but you'd still have tall spring saddles on the axle to clear the diff casing from the spring, creating the space for the standard Defender track rod behind the axle anyway.

Comments claiming improvement and handling benefits by owners who have done such bodged axle fits are invariably by people who are comparing a new axle and steering system to an old, worn out axle and steering system with a lot of slop and maladjustment, have no feel for driving and poor mechanical understanding, are hiding their cock-up or all three. I have seen so many bodged and butchered vehicles, especially Land Rovers, that I can sometimes see why the EU want to ban all mods.

Duncan, lift the axle as you have to anyway, use a Defender track rod (a Discovery or RRC rod has a damper bracket and length adjuster clamp which will foul the springs), and use the adjuster from a Disco/RRC track rod adjustment section with 1/2" removed from each end of it and the Series drag link to extend the drag link for the wider axle. That not only gives you a perfect drag link for little or no cost which can be replaced easily, but also allows steering adjustment without the hassle of removing the steering damper. It works beautifully. If you want to regain lost ride height, use more cambered springs or longer shackles, accounting for the new spring angle when you make the saddles, or do the same rear spring mod as Koos and that American did, which gives much improved articulation and smoother ride as well - Koos' front articulation is astonishing.

Front tyres always wear faster than rear tyres because of the lateral steering scrub and the greater front braking forces. As long as the wear is even across the tyre, then things are fine, but if you have uneven wear, then faults in tracking, camber angles, tyre pressures and so on are often causes. Rapid tyre wear occurs if you live near a lot of roundabouts, usually more on the near side tyre than the off side because of the vehicle weight leaning to the near side while going around them.

[Duncan]

Well if the axle needs to be lifted for the diff casing then that's fine if it has to be anyway, and tbh I'm all for keeping mods with standard parts for ease of finding spares and as designed to work.

I will have a good measure up in situ when I get my disco axles as with my front twisting mounts(on dumb irons) i think the front para is about level if not leaning forwards-Not ideal so might have to lift axle up more then look into adding a leaf

Cheers for all advice! I'm also going to write to DVLA as I would like clarification on where they stand, also if parabolics count as a change to the original vehicle point wise, Rocky mountain themselves don't know!

[ToyRoverlander]

also if parabolics count as a change to the original vehicle point wise, Rocky mountain themselves don't know!

IIRC Rocky Mountain is a Canadian bussiness so why would they care about the DVLA's view on parabolics..

Adding a 3rd leaf like Nick did is a good idea anyway

[Phil Hancock]

Parabolics are accepted as a direct replacement with no points lost as they fit exactly the same as the original leaf springs.

[Snagger]

Parabolics are accepted as a direct replacement with no points lost as they fit exactly the same as the original leaf springs.

That's what I was told too. It's amazing that on the rebuild points system, you can retain the points even though the springs have been replaced. The logic is that on most vehicles, the springs and dampers are service-replaceable components within a wider suspension ssytem, but on old Land Rovers, they constitute the entirity of the system, so we get an easier time of that part of the rules.

[Snagger]

I will have a good measure up in situ when I get my disco axles as with my front twisting mounts(on dumb irons) i think the front para is about level if not leaning forwards-Not ideal so might have to lift axle up more then look into adding a leaf

The front springs should sit slightly inclined if the chassis and shackles match, with the rear end of the spring slightly lower than the front. Fitting longer shackels would steepen that angle, so if you do that, factor it in to the new mountings on the coiler axle. Fitting a more cambered spring, like a tree-leaf parabolic, keeps the over all spring axis standard. However, a third leaf in a parabolic spring might be uncomfortable and lacking in articulation if your vehicle has standard weight - it works well on mine because I have a winch and wire rope, bull bar, bonnet mounted psare, front fuel tanks, steering guard and a lot of heavy (Noise Killer and Wright Off Road) sound proofing; the springs were nearly flat with just the standard two leafs.