Thread: Noob Questions Re: Axles and Diffs

I just put an auto locker in with standard axles and standard 235/70/16 tyres and the advice I got was I didn't need HD axles unless I was going to try something really extreme, which I'm not.
Do you really need 285/75/16 tyres? You'll need at least a 50mm lift like I have I imagine, although I'm not sure if you'll still need to cut the guards even with the lift to make the larger tyres fit.
The easier and cheaper way to get better traction would be to stick with standard tyres and axles and add a locker.

Originally Posted by harry

as i said in my first post, arb rear locker was fine with standard axles, i did many trips into hard stuff, but when i put big tyres on it the axles couldn't handle it.
put the rear locker in and use it, when an axle breaks, upgrade to heavy duty axles
unless you have big tyres

Yep, I understand Harry, thanks.

I've decided to just wait a while longer before going down the locker route. I'd like to do it properly first time, so I'm gonna put away some cash when I can to do it in the future.

My original thoughts were to transfer the HD axles, diffs and CV's out of a Rangie which already has them, into my Disco, hence my asking if the Rangie gear suits. I don't suppose you'd know if this is the case or not??

Originally Posted by DiscoMick

I just put an auto locker in with standard axles and standard 235/70/16 tyres and the advice I got was I didn't need HD axles unless I was going to try something really extreme, which I'm not.
Do you really need 285/75/16 tyres? You'll need at least a 50mm lift like I have I imagine, although I'm not sure if you'll still need to cut the guards even with the lift to make the larger tyres fit.
The easier and cheaper way to get better traction would be to stick with standard tyres and axles and add a locker.

Thanks Mick. I think the lift on the Disco is around 100 - 150mm, this is based on looks alone. I haven't worked out the exact lift from factory spec. It has a 50mm body lift, plus a suspension lift which I think is between 50 - 100mm.

Luckily, I live close to some of the best 4wd spots in Victoria (The Otways for one!!!) and yes, I would like to keep the MT117's on it.

Originally Posted by brenno

... Perhaps I need to talk to some people running standard diffs and axles with ARB lockers to see how they've found them.

The standard diff has a hemisphere with only 2 pinions (also called planet gears, or spider gears by some). The shaft that carries these pinions is arguably the weakest part of the rover drive line.

This shaft either breaks or comes adrift. When this occurs, extensive collateral damage usually follows due to the pieces of metal floating around and breaking teeth from the crown wheel and pinion. Bits often get propelled out through a hole they make in the rear of the casing.

All lockers for rover diffs that I know of replace the stock hemisphere and will overcome this weakness while offering great traction improvements.

As others have said, aftermarket axles won't improve your driveline strength, until you address the other issues.

The front 24/33 axles are possibly weaker than the 2 pinion diff, but in most offroad use, the rear diff sees much higher loads than an unlocked front axle.

Once you have lockers, the axles and cv's become your weak link. Then when aftermarket axles are fitted, the spiral bevel crownwheel and pinion become the weak link. Then ....

Originally Posted by brenno

... My original thoughts were to transfer the HD axles, diffs and CV's out of a Rangie which already has them, into my Disco, hence my asking if the Rangie gear suits. I don't suppose you'd know if this is the case or not??
...

They may or may not suit.

I will repeat some of what I said/implied before.

You have 24 spline diffs, 24 spline rear axles and 24/33 spline cv's.

You also have to find out if you have ABS.

Some rangies are 10 spline. When aftermarket axles are fitted, it is possible to change many things. Many have upgraded 10 spline rangies to 24 spline (though none I know have ever used 24/33 spline aftermarket front axles.

You will have to find out what axles and cv's are in these rangie diffs.

It would be possible to fit them to your disco, but some things would be silly, like swapping everything back to 10 spline.

Generally speaking Pre 88 model Rangy's will have the 23/10 spline type C.V. Joints. 88 models onward will have the weaker 33 spline C.V. unless it has been modified, and would only be the case if it had a front diff lock fitted.

Read on only if you wants to get really confused

The good thing about running the 23/10 spline C.V. if you do break one you can get going again quickly, by just undoing the 5 flange bolts on both sides remove the 10/24 spline half shafts, refit the flanges unbolt the front
prop Shaft and you are good to go again...Only rear wheel drive of course but hey! if you use any of the other C.V. types the Half Shaft is part of the C.V. so it's more expensive to replace.

Or you can use the original Rangie One Piece half shafts and they are the weakest link in the chain, and very quick to replace. A lot of Comp Trucks have a set up like this because its and easy quick fit to get going again. Albeit half shafts turns down on lathe to break at a more precise point.

Hey Brenno
I have a 94 V8i disco with front and rear ARB lockers, standard 24 spline axles. I am running 265/75/16's tyres and it has a 2.5" lift under it. I have had this set up for about 7 years and had no problems with it.

Except for exploding a front drivers side CV once in the mud, but all wheels were spinning in third high and doing about 5000 rpm, then the drivers side front got traction. In that situation I doubt any axle would have stood up to it, or if it did then the diff would have exploded. So long as you dont intend to do competition work with it then the axles should stand up to careful full locked situations. Just remember never lock up on the hard because then you will break more bits than you can believe.


I believe a winch first is a better option as it is a recovery aid, lockers are traction aids.

Hope I have helped

Blythe

Thanks heaps for all the info guys, I have learned a lot from this thread, and it becomes a reference point for those who need the info in the future too. Much appreciated.

I'm gonna wait for the lockers. I have a funding issue anyway... I have purchased a few accessories this weekend (compressor, UHF, lights, cargo barrier), I have a major service booked Wednesday, my rear brakes are stuffed, and I've just noticed a leaking hub/swivel seal on the left front too.

Once again, thanks to all who have contributed.

Originally Posted by brenno

Cheers Slunnie, well explained.

I certainly wont be mistreating it as it's an occasional daily driver too, so I can't afford to have it broke all the time. Having said that though, I'm not going to pussy-foot around when I'm out on trips either. Like you say, being sensible is the key really.

Perhaps I need to talk to some people running standard diffs and axles with ARB lockers to see how they've found them.

hi thats me, i just had arb lockers installed, the diff center that came out of the discovery was a pore design in that it has a week point, there is only one king pin in the spider gears, the arb has a 4 gear spider gear assembly with a 2 king pin type set up , eg 4 gears taking pressure rather than 2 gears in the standerd land rover. and if you look on youtube there are lots of broken pins when the diffs fail. second the arb has been designed to servive an axle failure. so if you do twist the crap out of the axles you know that you can swap it and your locker is still ok, i took my disco out today and couldent beleave the stuff i can just idle over that i cant come near when im huffing and chuffing with spinning wheels . also to coment on a previous quote, if you look on youtube most axle brakes happen when the wheels are spinning and the truck is bouncing, wich dosent happen with lockers. easy to say get a pair but i had to get a loan my self to get them and the rest of the gear. dont know how i got the misses to aprove it.