Mk1, MX-5 NA Gearbox types.

Technical Area Engine, Transmission, Exhaust etc
2

A friend of mine is on the look out for a gearbox for his mk1.

I understand there was an update somewhere about 1993 to improve the gearchange when cold on 1st and second gears, I assume this was on the synchromesh but can’t find information other than the gearbox code changed from “M-type” to “M15M-D” in 1993, or at least it did according to the service manuals on mellens website.

http://www.mellens.net/mazda/Mazda-Miata-1991-1993/1991_manual_transmission_overhaul.pdf

What I wanted to know, is there any external differences between the two gearboxes? I think they both have “M526” stamped on the side (but could be wrong on this), and understand they are both interchangeable, but thought there must be something to tell the two apart by looking at them.

Let me know if you have an idea.

3

Mazda might have attempted an improvement, but doesn’t mean they succeeded. I have had 91,92, 93 (x2) and 96 cars, and the gearboxes have all felt similar. If he wants the most recent iteration of the 5-speed, just source a Mk2 box, then there is no doubt.