Axle Ratio on a '80 Jimmy?

[rockinshovel]

Folks, I have burned up an axle bearing on my 80 jimmy. I have found what i believe to be every number on the axle and still can't find out which ratio i have...BTW there is no sticker in the glove box or on the door, they have long since been remove. Thanks for the help!

 

[dyeager535]

Pop the diff cover, the ring/pinion tooth count is stamped on the edge of the ring gear. Divide to get the ratio.

 

[onetonbb74]

What are you trying to do? If your replacing the entire axle with another and need to know the ratio, you can always check the front axle for a tag of some sort assuming the ratios match/ 4x4 worked. Your best bet is pull the cover and count the teeth or look for the numbers on the side of the ring gear. If your swapping a bearing, you still have to pull the cover to get the axle out anyway so id just pull the cover.

 

[shaun89]

i think ive said this before but hell, 2 times cant hurt. a way to find ur ratio without taking off the diff cover is to 1.make a line on ur tire and fender (lined up) 2. make a line on ur driveshaft near ur diff. and have some one turn the tire 1 complete rotation. make sure they get close to 1 rotation as they can. and while they r doing that. get under there and count how many times the driveshaft spins. for example if u spin ur tire 1 time and ur driveshaft spins a little over 4 times you have 4.10s. or if it spins a little over 3 times you have 3.08s. sorry if im a little confusing.

 

[trailblazr81]

i think ive said this before but hell, 2 times cant hurt. a way to find ur ratio without taking off the diff cover is to 1.make a line on ur tire and fender (lined up) 2. make a line on ur driveshaft near ur diff. and have some one turn the tire 1 complete rotation. make sure they get close to 1 rotation as they can. and while they r doing that. get under there and count how many times the driveshaft spins. for example if u spin ur tire 1 time and ur driveshaft spins a little over 4 times you have 4.10s. or if it spins a little over 3 times you have 3.08s. sorry if im a little confusing.

Isnt it x2 with an open diff?

• If you turn one tire & the other one either stays still while the pinion rotates, or the other one rotates backward while the pinion stays still, or something in between, then you've got an open diff or a very weak LSD (like a Trac-Lok with too many miles on it). In this case, you need to secure one wheel (perhaps by lowering the tire onto the ground), then you can figure your gear ratio by rotating the airborne tire TWO full rotations and counting the number of times the pinion rotates. 3.73 turns means 3.73 gears. If you only rotate the tire once, then 1.865 turns means 3.73 gears.
• If you turn one tire & the other one turns the same number of turns in the same direction, then you've got a good LSD or locker. In this case, you can just rotate the tires ONE full rotation and figure your gear ratio by counting the number of times your pinion rotates. 3.73 turns means 3.73 gears."

Also my 81 had 3.08's!! Woo-Hoo!!!

 

[shaun89]

i never actually thought about that, thanks!