I saw the thread here with all of the different differential covers but how do you tell what the gear ratio happens to be ? I searched threads here and couldn't find anything, I downloaded a DANA pdf and cannot decipher it. I have enclosed a picture of the cover that I removed to install a cleaner painted one but the numbers don't match. From what I can tell the bottom row is the date stamp but that is about it. Any info is greatly appreciated.

 

Check the rear also, there is usually a metal tag with more numbers. I have a 95, sport model, no tow package and I originally had 3.55 gears, D30 up front and Chrysler 8.25 rear.

 

Deduction; 1995 4.0L with AW4 automatic equals 3.55 gear ratio.

 

The numbers are meaningless as it relates to your gearing.

There is a tag that is bolted to it that relates to gearing and ID.

 

On the front I have a small metal tag that was bolted to the front of the cover but it is covered in so much crud I could not read it. @Cheddar, mine is pretty much the same except a country package. Thanks for the info all.

 

Try the tag on rear axle. 99.8% certain it is 3.55:1 ratio.

 

All those numbers are basicly just a casting code for the part its self.All parts have some kinda code on them for quality control and in case they have to recall something they can track it back.

 

Agree with Steve^^, very common axle ratio for that year. Just hit the crud with some cleaner and read the tag. Similar tag on the rear as well.

 

yep. those numbers mean nothing to us.

most stock 4.0 liter automatic jeeps are 3.55 from factory, but someone could've swapped gears or axles. best way is to pull the cover.

if you don't have the metal tag bolted between two cover bolts on the diff, then you would have to pull the cover and look on the edge of the large ring gear for the tooth count.

it will look like this. the numbers in blue is what you are looking for. simply divide the (larger) number (of teeth) on the ring gear by the (smaller) number (of teeth) on the pinion. so example 41 divided by 10 would be 4.10...




the number in yellow is the gear set number. that has to match the number on the pinion gear so the cut matching set is the same so it meshes properly.

 

If its completely stock Steve is correct.


If there is any doubt in your mind then this is the correct way. Gear changes cost money and most don't spend money on them for a stock XJ, just when they go with larger tires and a lift.

 

Thanks for all of the info, I am fairly certain that it is all stock. My swapping and painting of the differential cover was just one of those little things I wanted to do when I changed the fluids but I wanted to make sure that I was not removing something that had pertinent information on it. I am a ways away from doing any sort of lift, but thanks again for the help and insight.