Hey guys, another newbie question..............

How do I know which transmission, transfer case, and differentials are in my '92 XJ 4.0?

One reason that I ask is because I think the entire rear end has been changed. The PO said that it had, and it had some yellow paint pin numbers on it, like it had came from a junk yard (etc....).

Also, what gears typically came in them? Of course, the ratio tag is missing on both stumps.

It's got 35's on it and I'm considering a gear swap. Leaning toward either 3.73 or 4.10, but wanna know what I've probably got first.

 

Trans and xfer should have tags. Differentials can be identified by sight, and gear ratio can be determined by counting revolutions of driveshaft:wheels

If you have full-time and part-time 4wd: NP242 transfer
If you have only part-time: NP231

If you have an automatic, you have an AW4 transmission.

Do a search for differential identification and you'll find plenty of examples.