How can I figure out what gears I have?

[66nightMARE]

When I bought the car he said it had an 8'' rear, but didnt specify the gearing. Whats the easiet way to figure out what gears I have?

 

[67topless]

Here is a link to a site I've used before (Probably got it off a posting from Stangnet)... good luck:

http://www.woodyg.com/fairlane/finfo/fordrears.html

 

[gjz30075]

If you don't have the tag on the diff, then you need to count the number of turns the driveshaft makes to one revolution of a tire. I believe you then double your answer if you have an open (non posi) diff. ie, if your drive shaft makes 1 1/2 turns to one revolution of a wheel, then its a 3.00 to 1 ratio gearset.

Others should chime in with other methods.

 

[LMan]

why would you double your answer? An open/tracloc doesn't affect the ratio one iota.


Compare d/s revolutions to wheel revolutions.

 

[CochinoFilipino]

why would you double your answer? An open/tracloc doesn't affect the ratio one iota.


Compare d/s revolutions to wheel revolutions.

It does't affect the ratio but if you jack one side up with an open end and one tire is planted, the free wheel will spin twice. (like you're making a turn) 1x2

If you have LSD, you jack both sides up and both wheels will turn one rev. (like you're going straight) 2x1

If your pushing the car on the ground and both wheels are turning. 2x1


2x1=1x2

You are correct, count wheel revolutions. But sometimes people get confused and count only one wheel while both are turning.

 

[gjz30075]

Thanks Cochino for the better explanation of what I was assuming

 

[67Dylan]

If you don't have the tag on the diff, then you need to count the number of turns the driveshaft makes to one revolution of a tire. I believe you then double your answer if you have an open (non posi) diff. ie, if your drive shaft makes 1 1/2 turns to one revolution of a wheel, then its a 3.00 to 1 ratio gearset.

Others should chime in with other methods.

That is the way I was taught and has never been wrong.