How to find out Axel Ratio?
JK Jedi Master
Joined: Jan 2008
Posts: 11,463
Likes: 165
From: Austin <--> Colorado Springs
Here is a link to help you identify which axles you have.
http://project-jk.com/jeep-jk-tech/j...er-axle-basics
http://project-jk.com/jeep-jk-tech/j...er-axle-basics
JK Super Freak
Joined: Apr 2008
Posts: 1,231
Likes: 0
From: Guam - PCSing to McGuire AFB, NJ in July '09
JK Jedi Master
Joined: Feb 2008
Posts: 12,904
Likes: 185
From: Maine
Ya is there any way to Id you ratio, beside build sheets which I do not have right now (in progress)? I have the 2007 jeep 2-door X stick which has two choices 3.21 or 4.10.
I have searched and could not find any on this...
If not I guess I will just have to wait till I get me sheet…
Thanks guys!!
I have searched and could not find any on this...
If not I guess I will just have to wait till I get me sheet…
Thanks guys!!
This was posted by Ronjenx:
Chock the front tires, fore and aft.
Put the transmission in neutral.
Emergency brake off.
Jack the left rear tire off the ground.
Put a jack stand under the frame, just in case the jack fails (had to add this).
Put an index mark on the aft end of the drive shaft, visible from the left rear wheel.
Put an index mark on the left rear tire at the 6 o'clock position.
Rotate the left rear tire 2 complete revolutions while counting how many times the index mark on the drive shaft passes its original position.
That number will be your axle ratio.
Remove jackstand and lower jack.
Put transmission in gear and/or apply emergency brake.
Remove chocks.
If you have limited slip, jack up both rear wheels and rotate one revolution, making sure both tires rotate equally.
If the driveshaft rotated almost 3 1/4 turns, you have 3.21
If the driveshaft rotated almost 3 3/4 turns, you have 3.73
If the driveshaft rotated a little over 4 turns, you have 4.10
Chock the front tires, fore and aft.
Put the transmission in neutral.
Emergency brake off.
Jack the left rear tire off the ground.
Put a jack stand under the frame, just in case the jack fails (had to add this).
Put an index mark on the aft end of the drive shaft, visible from the left rear wheel.
Put an index mark on the left rear tire at the 6 o'clock position.
Rotate the left rear tire 2 complete revolutions while counting how many times the index mark on the drive shaft passes its original position.
That number will be your axle ratio.
Remove jackstand and lower jack.
Put transmission in gear and/or apply emergency brake.
Remove chocks.
If you have limited slip, jack up both rear wheels and rotate one revolution, making sure both tires rotate equally.
If the driveshaft rotated almost 3 1/4 turns, you have 3.21
If the driveshaft rotated almost 3 3/4 turns, you have 3.73
If the driveshaft rotated a little over 4 turns, you have 4.10
JK Jedi Master
Joined: Feb 2008
Posts: 12,904
Likes: 185
From: Maine
This question keeps coming up and people still refuse to get the direct answer, which would be uninfluenced by other variables.
Dealer info could be wrong
; a previous owner could have re-geared; etc., etc.He had his answer in post 3.
JK Jedi
Joined: Feb 2008
Posts: 7,215
Likes: 10
From: Georgia
Easy to do, but still could be only a guess.
This question keeps coming up and people still refuse to get the direct answer, which would be uninfluenced by other variables.
Dealer info could be wrong; a previous owner could have re-geared; etc., etc.
He had his answer in post 3.
This question keeps coming up and people still refuse to get the direct answer, which would be uninfluenced by other variables.
Dealer info could be wrong
; a previous owner could have re-geared; etc., etc.He had his answer in post 3.
Thread Starter
JK Newbie
Joined: Apr 2009
Posts: 18
Likes: 0
From: MI
Hey guys thanks for all the great info, thanks dmhines, your way was quick and easy!! Not like the other way was awful hard either But no one answered my other question how much is it to make it a 4.10 if it is a 3.21? Thanks again…
JK Super Freak
Joined: Apr 2009
Posts: 1,633
Likes: 0
From: Forsyth County, GA
I have heard between $1200 to $1500 parts and labor ... keep in mind both axles need to be changed ... so parts and labor are doubled ... and I'm sure most folks add a limited slip at the same time if you don't already have one.