Have a look at your VIN plate, the bottom row has 4 groups of numbers. The 3rd group will say which diff you have on the rear. 4.300 or 4.100 and if its LSD, manual or open
It won't tell you the front diff ratio but it has to be the same as the rear if its a permanent 4wd.
diff codes;
4.100 diff no LSD possibly manual lock A01B
4.300 Diff no LSD possibly manual lock A02B
4.300 Diff with LSD A02A
4.100 Diff with LSD A01A