Thread: 10-spline maxidrive axels vs 24-spline std

Considering that oem 10 spline have been proven stronger than oem 24 spline because of material, I'd say it a safe bet. You can always up grade the MD to MD 24 down the track.

The 24 spline axles have better geometry and are less prone to fatigue cracking failures where the splines start. Ashcroft tests show the 24 spline were about 20% stronger than stock 10 spline in a single twist to failure.
Where the Maxi-drive axles will be stronger material and will take more torque in a single twist to failure.

Are you swapping entire axle assemblies or just the innards?

Originally Posted by uninformed

You can always up grade the MD to MD 24 down the track.

Could you? I didn't think you could get the parts to convert the locker anymore.

would the old 10 spline axles be a 28 spline side gear? if that needed swapping out Im sure something could be sourced. Between MR Automotive, the new MD locker producers and Barry of Hi-Tough Engineering (axle and drive flange maker, formaly of the original MD) I would think the components be able to be had.

Dougal, I thought that the Ashcroft testing showed that the OEM 10 splines were actually stronger than the OEM 24. Simply because of material of coarse.

MD axles are made from Hi-tuf, which is similar to 4340 300m, which both of these are superior to 4340 (which alot of better aftermarket axles are made from)

BTW Jarrod, I would be checking the condition of the internals if possible....dont just take the sellers word

Originally Posted by uninformed

would the old 10 spline axles be a 28 spline side gear? if that needed swapping out Im sure something could be sourced. Between MR Automotive, the new MD locker producers and Barry of Hi-Tough Engineering (axle and drive flange maker, formaly of the original MD) I would think the components be able to be had.

Yes I think the 10 spline axle would have the 28spline side gear which is the holden one I believe (which you can get still I think?).

I do however believe that currently there is no avaialbility of the 24 spline side gears (and hasn't been for a while). I know of several 24 spline maxidrives sitting in sheds with broken side gears, which have rendered them unusable.

maybe someone should do a production run!

Originally Posted by uninformed

Dougal, I thought that the Ashcroft testing showed that the OEM 10 splines were actually stronger than the OEM 24. Simply because of material of coarse.

Here are their test plots. The 24's on the rear take more force to break and twist a lot further before breaking.


The 24's on the front have broken with less twist, but the torque to break is the same. The 10 spline axle yield point is lower, showing the 10 spline axle has permanently twisted at a lower torque than the 24 spline.


But single twist to break doesn't tell the whole picture. On a 10 spline axle the splines are the weakest point which can lead to fatigue cracks. On a 24 spline axle the splines are bigger diameter than the axle shaft whic avoids the stress concentration and cracking that results.

I went 24 spline for two reasons.
1. My old axles had a lot of km in them.
2. All aftermarket shafts and diffs are now 24 spline. It makes future upgrades easier.

Im pretty sure that the MD 10 splines will be waisted ie better design....

If it is side gears, I would be calling MR Automotive and asking about availabilty. They need them made for their new MD lockers.