Gear Ratio

[XJLafonda]

What is the stock gear ratio for the Chrysler 8 1/4?

I've got one sitting in my back yard, and I don't trust the D35 that's under the jeep. I'm just trying to check it will bolt up without having to change the front axle with it.

 

[Evan463]

what did it come out of? auto/man

 

[Yucca-Man]

It's typically 3.55, especially if it came out of an automatic-equipped XJ.

Might be good to open it up and check.

Jim www.yuccaman.com

 

[Crabapple]

90% of the time
Manuals are 3.07s
Automatics are 3.55s

 

[kujito]

Might be good to open it up and check.

How does that work? I've never done any gear work and don't plan on any soon; would just like to know. The only way I know is to jack it up and count tire rotations vs. drive shaft rotations, and that's not exact. That obviously wouldn't work on an axle not on a vehicle.

 

[cherokee chuck]

Take of the cover & count the teeth on the ring & pinion then divide the big number[ring] by the small number [pinion] & the answer is your ratio. Of course, it would be easier to look for the tag, It'll be stamped 3.07 or 3.55 with assorted other numbers on it.

 

[poorboy_616]

Also, get one side in the air (if it has an LSD, then both sides), put a reference mark on the tire and Driveline, then spin the tire and count the revolutions of the driveline.

Just over 3 1/2 turns of the driveline per 1 turn of tire would be ~3.55:1

 

[Yucca-Man]

Take of the cover & count the teeth on the ring & pinion then divide the big number[ring] by the small number [pinion] & the answer is your ratio. Of course, it would be easier to look for the tag, It'll be stamped 3.07 or 3.55 with assorted other numbers on it.

It's also stamped into the ring gear.

Also, get one side in the air (if it has an LSD, then both sides), put a reference mark on the tire and Driveline, then spin the tire and count the revolutions of the driveline.

Just over 3 1/2 turns of the driveline per 1 turn of tire would be ~3.55:1

Go 10 turns on the tire - it helps eliminate "close" ratios...you know for sure whether it was almost 31 (3.07) or 35 (3.55) ratio.

Jim www.yuccaman.com