99 speedometer calibration?

so i have a 99 with 4.0 aw4 and i believe a 231? (no full time) my question is this.... with 35's and 3:55 gearing (dana 30 and 8.25) my speedo is way off... do i need to put in something like the superlift tru speed to correct this or is it in the transfer case? and to complicate things more i'm going to install a transfer case from an 03 rubicon tj as well so would the fix work for that case as well? thanks in advance!

On the XJ transfercase, the speedometer gear is located on the top of the case, on the drivers side (you'll see the plug going into it, with two bolts holding the bracket into place). Simply unbolt, snap off old gear, snap on new gear, and make sure you re-install rotating the assembly to the proper position for whatever new gear you've installed. Search around on here, there's plenty of good write ups on how to do it (takes all of 5 minutes to change them out).

As for the 03 case you're about to swap in, i'm not sure where it's located but I would imagine it to be in the same place with the exact same procedures.

The wires connect to your speedometer gear. You will have to figure out what tooth count you will need. This might help you... http://www.superlift.com/library/gears.asp

ok cool... thank you!