I finally got around to taking some pics and measurements.
On the left, is a T18 Axle, 23 tooth spline, 24mm OD on the splines, On the right is a JDM Zenki Disk brake axle, 23 tooth, 24mm OD on the splines.
The big difference of course is the bearing size, T18 having the smaller, narrower bearing, and JDM having the big bearing. I dont see how you could fit JDM bearings onto a T18 Axle, as the axle shaft begins to taper right from the spacer, before the first step, so a t18 axle can only accommodate a t18 bearing setup.
Also note the hub mounting face size is different, probably due to the fact the disk brake hat has to fit over the JDM axle.
Both axles are the same in end view
But the JDM axle is actually shorter (approximately 4mm)
You can sort of see the difference here
Measured from the wheel mounting face, to the tip of the axle, the JDM axle is approx. 684mm, the T18 axle is approx. 688mm. The T18 axle was definitely from an open centre diff originally, but wheather the JDM axle was from a factory LSD diff is unknown.
I've taken off my open diff of my car, it has no lsd, got big bearings, comes with disc brake, n got 23 spline on the shaft.
n i bought another axle with lsd, comes with drum brake, but with small bearing setup, which look exactly same as the T18....
the one comes with drum brake shaft is a little bigger in diameter than my big bearing disc brake shaft, n now i'm trying to use my thinner shaft to fit into the larger diameter lsd axle, is that viable?
i want to change to lsd axle, where i want to keep the disc brake set up, any idea of how can i make it?
I'd really like some confirmation with this. I need to know for sure which diff I have as I need to rebuild my centre (or replace it).
I've been reading everything I can find about how to tell the difference between the two diff series (zenki and kouki) but there's too much conflicting information.
Here are some closeups of my axle.
Some people say the zenki axles have 23 splines and the kouki axles have 24 splines, some people say they have the same number of splines.
Some people say the axle tapers twice for zenki and once for kouki.
Some people say zenki have rings on the end of the axle and kouki have lines.
My diff has 23 splines., rings on the end but only appears to taper once. I measured the diameter of the axle (not at the splines though. Doh!) with my dodgy plastic measuring calipers and got 25-26mm on the axle diameter. It appears the axle diameter is bigger than the axle spline diameter, if that helps.