ctjkelley

How and what is the easiest way to tell what my gear ratio is? I will be swapping from a C8.25 to a F8.8 soon. The 8.8 is already in a XJ and I just want to make sure that my D30 front is compatible with the 8.8 or if I will have to swap the front as well. Thanks

motorcharge

Jack the Jeep up. Turn the wheel and count how many times the driveshaft turns per wheel turn and that's your ratio. Obviously not exact, but if it turns 3.5 times you likely have 3.55 or something close to it, slightly more than 4 times 4.10, ect, ect.

ctjkelley

Thanks...I will have the diff cover off inspecting. How can I tell when I pull the diff cover off?

motorcharge

Should be stamped on the ring.

ctjkelley

Thanks will take a look at it

motorcharge

Here's what they look like, pretty easy to spot.

SeriousOffroad

I know many of you have looked at the picture above and wondered what the multi-toothed-gear-thing-a-mah-bob is....but you're afraid to ask for fear of looking like a newb.

Well here's your answer...

We all know that FORD stands for Found On Road Dead. Ford engineers and designers were tasked with finding a way to keep the Ford name from getting drug through the mud every time one broke down.

So.....
What you don't see is the bicycle chain that is normally connected to both the accelerator and brake pedals.

When a Ford breaks down, the owner can rapidly pump both pedals (similiar to a bicycle) until he arrives at an authorized repair facility.

A lesser known fact is that with the phenomenal popularity of the Ford Model T, prostitutes were able to broaden their "Sales Area" and generate a substantial income. Because of the accelerator/brake pedal modification, hookers were always able to peddle their azz all over town in a broken down Ford.

ctjkelley

Yes I believe I will be able to spot this. Thanks for the pic they always help as I am new to doing these things.

mr white

If you have a 5spd with the 4l you have 3.07. If you have the auto, 3.55.
Also there might be a tag still on the diff cover bolt which will also tell you.

mr white

:thud:

sneakyjap96

Driven divided by drive teeth count will tell u

ctjkelley

Not sure what you mean by driven??

sneakyjap96

The drive is the pinon gear aka it drives the ring gear so the ring gear is the driven so take the ring gear number and divide it but the ring gear. Ex 40 teeth on ring÷ 10 teeth on pinon = a 4 to 1 ratio

ctjkelley

Understood ....thanks