This conversion is to upgrade the front or rear axles of 10 spline coil sprung Rovers (Range Rover 1987 to roughly 1993, Defender 110s and Defender 90s) to a stronger, thicker axle shaft with more spline contact area. The conversion will mean that in some cases you can not run alloy wheels due to the thicker drive flanges that are used. The 24 spline heavy duty axles can also be used in place of stock 24 spline axles (as in Defender 90s) as the units are stronger overall and better suited to use and abuse with lockers of all types.

The basic goal of any off road vehicle is to be able to traverse the desired terrain without breaking anything. As your 4 Wheeling desires grow, the type of terrain you ride on gets harder and harder. A good step to make your Rover more capable off road is to install differential lockers of some sort. A locker like an ARB Air Locker can transform your Rover into a vehicle with true 4 wheel drive (rather than just one wheel per axle). That is the good news. The bad news is that with a locker the stress put on the axle shaft itself is increased. This means that as you travel that extreme terrain your axles may not stand up to the stress put on them. All lockers put extra stress on the axles, no matter what type (ARB, Detroit... all lockers) and eventually you'll break an axle. Trust us, you will... we've broken dozens and we don't even drive with a lead foot, we mainly just do slow speed rock crawling.

So what can you do about it? Arm yourself with the best equipment going and upgrade your axles from the stock 10 spline axles to the ECR heavy duty 24 spline units. By using the 24 spline units you will get a number of benefits:
1. A larger diameter axle (harder to break)
2. An axle made out of better raw materials (harder to break)
3. A heat treated axle (harder to break)
4. A multi spline contact area (harder to spin the splines)
5. A thicker drive flange (more contact area)
6. A stronger CV joint that is rated for 1 ton Rovers (much stronger) *front axle only

The axles are simple to install and can take another worry out of your off road adventures. No axle is "unbreakable" but if you drive with common sense and have the best equipment going, you have a good shot at getting through the trails when your buddies Rover is side lined with a snapped half shaft!

ECR recently did another 24 spline conversion to a NAS Defender 110 and we took some comparison photos this time to show you what everyone is talking about regarding 10 spline vs. 24 spline axles.
10 vs 24
This image shows the inner axle (differential side) of a standard 10 spline axle (top/left) as you would find in a 1987-1993 Range Rover or in the front of a NAS Defender 110 in this case. You can see that when compared to the HD 24 spline conversion axle (bottom/right) that the 24 spline unit is much thicker and has a lot more contact area with the differential. This is just part of what makes the axle stronger and better able to suit life in a Rover with lockers. Previously in one season of off roading with a 1987 Range Rover with the standard 10 spline axles the ECR staff broken upwards of 7 axles. When the same vehicle was converted to HD 24 spline axles we stopped breaking axles completely. The 24 spline axle has more splines, a thicker contact area and the axle shaft itself is much thicker as well, a win, win situation.

On the rear axles the new drive flange is almost half again as wide as the stock unit This gives a stronger flange, more contact area and when set up with the HD 24 spline axle it makes your rear axle as close to bulletproof as possible. We have rear axle kits available for all 10 spline Rovers including Series Rovers, so feel free to contact ECR with your axle needs.

The front axle of a coil sprung Rover incorporates a CV (constant velocity) joint. The 10 spline axle CV joints also suffer from premature detonation. Too much stress from a front end locker, or even just too much throttle and too many miles can blow your CV joint splines or cage and leave you stranded. Those of you who have torn down a CV joint on the trail know that it is not a fun job, especially when you are up to your knees in mud. A 24 spline HD front end axle conversion and CV joint upgrade can help solve all these problems.
CV side 24 vs 10
This image shows the outer end of the front axle half shafts (CV side). The left axle is the 24 spline HD unit and the right axle is the standard 10 spline unit. As you can see the size of the axle, the quality of the metal and the splines are going to serve you much better than the stock units.
CV joints
Here you can see the difference in the CV joints. The unit on the left is the 1 ton CV joint, the HD unit. The unit is the strongest currently made for the Land Rover front axle and will be the best thing for your locked Rover.

Here the installed axle set up tests out its capabilities on the ECR RTI ramp. You can see the large axle flange and axle cap that are part of the conversion kit clearly in the center of the wheel. This extra strong axle flange is also the reason an alloy wheel can not be used, the flange is so large and tough, it will not fit behind the alloy.

What about my differential you say? Well if you are upgrading to a locker of some sort, it is a lot easier to do a full upgrade the first time, than it is to learn the hard and costly way. If you installed an RD03 (10 spline ARB locker) in your Range Rover and then wanted to later upgrade to 24 spline axle because you found you were breaking axles, your RD03 would be useless. You would have to remove it and install the RD128 ARB locker (24 spline) instead. A costly mistake. The RD128 locker will fit in the original differential case in just about any Land Rover and you can easily set up your originally 10 spline Rover to have 24 spline axles front and rear.

Installed in your Rover by our full time professionals, this 24 spline axle upgrade is what we suggest to make your axles as tough as possible at a reasonable cost.
110 twist
Let us know if we can help you with any of your off road upgrade needs>

Please note we do not offer mail order axle sales.

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