Miata Rear Spindles/Axle spline count

Hello All,

You can skip to the last paragraph to avoid my tale of woe.

You may remember a while back that I had a fight with a pair of miata rear spindles. (http://grassrootsmotorsports.com/forum/grm/removing-lower-control-arm-bolt-miata/59429/page1/). Today I admit defeat. I moved into a new shop with a plasma cutter/TIG/MIG/full size compressor etc. So I thought, "self, today is the day that I get those damn bolts off."

Ran over to our good friends at Harbor Freight, I should've taken the quite grumpy custom service as a sign of things to come, but I just took it as their normal manners. Picked up an air hammer, some nice drill bits, and set of reverse bits for removing stuck bolts. Armed with arsenal of tools, I was confident the bolt would bend to my will in no time. I drilled it with an huge ass drill press, I smacked with the air hammer for 30 minutes, I welded a bolt to the remaining bolt and attacked with an impact wrench only to have the bolt head (Grade 8!) come flying off..... (at least my welds held). No results, nothing but a very sad looking spindle with a bolt corroded to the inside of it.

So, I know when I'm beat, but that leaves me needing a pair of rear spindles for my locost. Which brings me to the point of this ridiculously long post. Do most generations of Miatas share spline count? How about brake caliper swappability? I think these were from a 93 or 94 miata along with my axles and rear diff, but I found these online. I'm sure I could do "better" in a junk yard, but these have free shipping and the cursed bolt already off. Will I run into any other issues or are these a fine fit? Sorry if any of this is obvious, I'm not really in the know with Miatas (don't throw things at me).

Thanks for the help!

Any spindles from a 1990-97 will work. Even the 1999-05 will, but they'll give you an extra 5mm of track per side. Calipers will bolt on in both situations.

Keith Tanner wrote: Any spindles from a 1990-97 will work. Even the 1999-05 will, but they'll give you an extra 5mm of track per side. Calipers will bolt on in both situations.

Thanks! That's the news I was hoping for! I can use 90-05 brakes/spindles; is there any "better" brakes or spindles or are there for all intents no differences between those in the range?

NB Sport Brakes are the "better" brakes.

Three different diameters of brake rotors, two different sizes of rear piston. All interchangeable - the rotor, caliper bracket and pads need to be matched, and you can swap in either rear caliper on those brackets. The size of the dust shield on the upright changes depending on the size of the rotors originally fitted, but a couple of minutes with a cold chisel will take those off so it doesn't matter.

Swank's oversimplified a bit - the NB "Sport" (optional from 2001-02, standard for 2003-05 in the US) have the biggest rotor and the largest rear piston, so they'll generate the most braking torque for a given line pressure. They're also heaviest, use the most expensive consumables, require a larger wheel and will give a slightly softer pedal