Does this work for finding gear ratio?

[mrk5]

I had the wife drive the truck forward slowly and I counted the number of times the drive shaft rotated in one full rotation of the tire.

Came out to three.

That'd be 3.08's, right?

Isn't that what all CUCV's came with?

 

[RustBuket]

Yeah, I think that would work.

 

[doctor4x4]

I have never heard of being able to do it that way
your close with your idea though
here is the way i have been tought and what works for me on a weekly basis
there are lots of variables to consider but here is a quick check that is usually 90 % accurate as long as ya dont have
a locker or welded your gears ( lincoln locker )
1st jack up ONLY THE PASSENGER SIDE rear TIRE
MaKe SURE the drivers side rear does NOT - can NOT turn !!!
2ND BLOCK THE FRONT TIRE TO MAKE SURE TRUCK WONT ROLL FORWARD
3. RELEASE PARKING BRAKE AND PUT TRANNY IN NEUTRAL
4 PLACE THE VALVE STEM ( I LIKE TO USE THE 6 OCLOCK POSITION OR 12 OCLOCK
5 MARK THE DRIVE SHAFT AND PUMKIN WITH A STRAIGHT LINE ( so you can get a VERY accurate count of how many time the drive shaft really turns )
6 rotate the wheel 1 full revolution at the same time COUNT the number of times the drive shaft turns
it will probably only be a little over 1 .5 time's
and then double that nu# vloia ya have a real close true ratio
example
1.5 drive shaft revolution x 2 = 3 hence the closeest factory set up is 3:07 so then ya really do have 3 07 gears as ya guessed in the first place
1.75 revolution x2 = 3.50 closet factory is 3: 42
allmost but not quite 2 full reloutions = 3:73
just a hair over 2 revolution = 4:10's
etc, etc etc
BUT B U Y FAR THE B E S T IS TO OPEN UP YOUR COVER CHECK TO MAKE SURE ALL IS GOOD IN THERE AND JUST READ THE NUMBERS OFF THE RING GEAR
IF YA SEARCH YOU WILL FIND AL THE INFO ON HOW TO READ THE RING GEAR INFO THEN YA REALLY KNOW WHAT YA GOT
hope it helps and happy wheeling
R

 

[K5MONSTERCHEV]

Yes it works.

 

[big83chevy4x4]

i like that way, but i always turn it TWICE, that way you dont have to double it and gives a more acurate reading.

its hard to tell the difference between 1.5, 1.70, and 1.85 turns but its easier to tell from just a hair over 3, 3.4, and 3.75 turns /forums/images/graemlins/waytogo.gif