Axle ratio
Elder User
Joined: Sep 2011
Posts: 979
Likes: 4
From: Vancouver
Firmly set parking brake.
Jack up one side only of the rear axle.
Install jack stand.
Put transmission in neutral - do not start engine.
Mark driveline with light colored marker so you can see the mark from the rear wheel that is jacked up
Mark the tire of the rear wheel at a convenient spot.
Turn that tire until the driveline makes one complete revolution while counting the number of times you turn the tire.
The # of turns will be the axle ratio. Larry
Jack up one side only of the rear axle.
Install jack stand.
Put transmission in neutral - do not start engine.
Mark driveline with light colored marker so you can see the mark from the rear wheel that is jacked up
Mark the tire of the rear wheel at a convenient spot.
Turn that tire until the driveline makes one complete revolution while counting the number of times you turn the tire.
The # of turns will be the axle ratio. Larry
Cargo Master
Joined: Apr 2007
Posts: 2,333
Likes: 1
From: St. Louis, Mo.
You might be able to find it on the rear pumpkin. Should be a metal tag with numbers on it. Others will be along with the codes for you. This is the easiest way to tell - Mine was stamped 373L- L for limited slip diff
Duct Tape Tech.
Joined: Jul 2009
Posts: 2,381
Likes: 1
From: San Antonio Tx.
Firmly set parking brake.
Jack up one side only of the rear axle.
Install jack stand.
Put transmission in neutral - do not start engine.
Mark driveline with light colored marker so you can see the mark from the rear wheel that is jacked up
Mark the tire of the rear wheel at a convenient spot.
Turn that tire until the driveline makes one complete revolution while counting the number of times you turn the tire.
The # of turns will be the axle ratio. Larry
Jack up one side only of the rear axle.
Install jack stand.
Put transmission in neutral - do not start engine.
Mark driveline with light colored marker so you can see the mark from the rear wheel that is jacked up
Mark the tire of the rear wheel at a convenient spot.
Turn that tire until the driveline makes one complete revolution while counting the number of times you turn the tire.
The # of turns will be the axle ratio. Larry
Butt-Head
Joined: Apr 2004
Posts: 9,457
Likes: 2,938
From: Reed Point, MT
This will NOT give you the gear ratio.
Any time the tires on a "differential-ed" axle are turned at different speeds (in the aforementioned case, one completely stopped) the ratio of driveshaft:tire will be different than the actual ring and pinion ratio due to the side and spider gears rotating around one another. In some instances, the gear ratio from driveshaft to tire can be as high as 2:1 using the "one tire spinning" method.
Any time the tires on a "differential-ed" axle are turned at different speeds (in the aforementioned case, one completely stopped) the ratio of driveshaft:tire will be different than the actual ring and pinion ratio due to the side and spider gears rotating around one another. In some instances, the gear ratio from driveshaft to tire can be as high as 2:1 using the "one tire spinning" method.
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Joined: Aug 2009
Posts: 12,467
Likes: 58
From: Missouri
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