Rear Gear Calculator

[07GtS197]

I can’t find the calculator that used to be on afm. I’m trying to figure out what gears I have in my 02 gt. They don’t seem to be that steep but I’m pretty sure they aren’t factory.

 

[lwarrior1016]

Mark the driveshaft and rotate the wheel. Count the driveshaft rotations for the 1 whelk rotation.

 

[07GtS197]

I might have to do that. Problem is it’s at my parents house and I don’t have concrete to put jack stands on. I found a formula online too, I’ll give that a try as well. The thing is, the calculator says I should have around a 4.10 ratio. At 60 it’s at just under 2k rpm’s. My 00 gt had 4.56s and I remember it being a lot higher. And I feel like this one is a bit of a dog, but that could also be from the crappy typhoon intake.

 

[joemomma]

There's one on LMR I think that uses speed, tire size, etc. I'm right at 2K at 60 with 4.10s in my '94 (4.10 is my best guess based on my GPS speed, tire size, and transmission). I haven't tried to mark the driveshaft yet.

 

[07GtS197]

Given we have the same tire size, we both have 4.10s. I have 285/40r17s on the rear.

 

[RAU03MACH]

Spicer Gear Ratio Calculator

The Spicer Gear Ratio Calculator will assist you in determining the ratio between the ring gear and pinion gear in the differential housing in the rear end axle of a vehicle.

spicerparts.com

 

[RAU03MACH]

Differential Gear Ratio Calculator | West Coast Differentials

Differential Gear Ratio Calculator Tools for Tire Diameter, RPM, and Gear Ratio from the technical experts at West Coast Differentials

www.differentials.com

Look to the bottom of page
This one has all including tires size and transmission speed