Outer Limits 4x4 Board

hey guys new to the forum just have a few questions. ive bought a 60 series front diff to go into my 75 series ute once i do a spring over and i wanted to know how to find out what size diff gears it has in it so i can match it to the rear of my 75 diff which i also need to find out. any help would be great cheers chachi

Count the gears on the crown wheel and divid the pinion into the crown wheel for ratio...
Eg 39 teeth on a crown wheel and 9 on a pinion is
39 / 9 = 4.3333... ratio is 4.3...

If its still in the car jack it up and turn the wheel a full rotation and see how many times the tailshaft turns you can work it out pritty close like that too.

Wow thats simple haha thanks alot mate

Providing its a standard diff center it should be a 4.1:1 and should be the same as the rear of your 75. As far as I know all 75/60/40 series were the same ratio apart from the really old 40's which were 3.7:1 I think.

ok thanks mate im gunna pull them both out and check anyway. dont wanna have everything binding on me
cheers for the help fellas

If you are going to pull the gears, once the centre is out, rotate the crownwheel look carefully and on the outer edge the ratio will be stamped...

RED60 wrote:If you are going to pull the gears, once the centre is out, rotate the crownwheel look carefully and on the outer edge the ratio will be stamped...

Only if there still factory gears... havent seen an after market set with them stamped into it for a long time...

macarthur 4x4 wrote:Only if there still factory gears... havent seen an after market set with them stamped into it for a long time...

My Nitro's and Yukon are all stamped.

91Mav wrote:

macarthur 4x4 wrote:Only if there still factory gears... havent seen an after market set with them stamped into it for a long time...

My Nitro's and Yukon are all stamped.

OK my nitro's were never stamped...

Different batches maybe?