How to tell what gears you have?


Say if you bought 4.10 gears for your Mustang, but the seller didn’t know they were 4.10 gears, how would you go about finding out?

I know you can count the teeth on the gears, but what’s the correlation between that and determining what the final would be?


of teeth on the ring gear / # of teeth on the pinion

also the ratio is usually stamped somewhere on them as well