Anyone have a good resource to illustrate setting backlash in a diff? This isn't Miata specific, just a project I'm working on.

 

It depends on the type of differential. Ford 9" is the easiest, as you can adjust just by tightening. GM is a bit more annoying, as you have to use shims. What sort of diff are you working with?

 

Out of a diesel Cub Cadet garden tractor. I'm transferring the internals from the stock and shitty Aluminum rear end to a cast iron casing. The service manuals assumes you know how all this stuff works, so they skimp on the actual how-to part of it and just say 'set the backlash between 0.003 and 0.008' and go to the next step.

Bad photo but here it is:

 

What's holding the ring gear in? You might have to set the backlash with the pinion.

 

There's two carriers that hold the casing in place, and the ring gear is riveted to that. The outside carriers are shimmed to set the pre-load/backlash.

After looking around I gather that I need to put a dial indicator on the ring gear, and turn the pinion to check the measurement?

 

Yep, that's right. This one works the same way as a GM. Are you messing around with the pinion at all?

 

No, just moving it from the Al case to the CI case, but supposedly it's done without modifying anything on the pinion at all.

Thanks for replying! I know it's only a small tractor but I want to try and get this done correctly instead of just throwing it together and then crying later when something bad happens.

 

No problem. Sounds like you figured it out on your own though.