Gear Ratio

I read in another thread that there is a metal tag on the rear-end of the Mustang that will tell you the gear ratio. I looked at mine the other day curious to see what ratio I have and I couldn't figure what the ratio was the only thing that stood out as being a ratio was 2 23 but I really don't think I have a 2.23 gear ratio... What am I supposed to look for?

I'm assuming it was pretty corroded. It probably said 2:73, which was a very common stock gear.

I might have just read it wrong. It wasn't corroded at all, it was in perfect shape just a lil dirty, but I wiped that off... I was also reading it sideways so maybe I did just read it wrong. I'll check tomorrow. Thanks... although I was hoping for 3.08's but oh well

Check the sticker in the drivers side door jamb.



M (I think) corresponds to a 2.73
Z corresponds to a 3.08
E corresponds to a 3.27

I swiped this info from another forum, so I can't be sure how accurate it is, and it was for 94-95 stangs. Maybe somebody here can elaborate further on it.

Also, unless your the original owner of the car, you don't know if someome switched the gears or not. That being the case your next best bet is to do this:

Jack the rear of the car up, put a mark on the drive shaft and spin the tire one full revolution. While spinning the tire, count how many times that mark goes around. If it goes around slightly more than three times, you have a 3.08 gear. If it goes around two and three-quarter times, you have a 2.73 gear. So forth and so on.

If you really want to know the exact ratio, take off the rear cover and count the teeth on the both the ring gear (the big one) and the pinion gear. Mark the first tooth so you can keep track of where you're at. Once you have the numbers, figuring the ratio is just a math problem. Divide the number of ring gear teeth by the number of pinion gear teeth. Example: 41 / 10 = 4.1