No its your Van and you can do as you like to it. But on the scanner it would ask for what diff was in it as it knew the gear ratio by which diff was in it so with the gear ratio changed by you in the stock diff I dont remember what other option it gives. Back when I was still at the dealer (I retired in 2011) the scanner did not ask for gear ratio it just asked for which diff was in it and tire size or revs per mile. But the scanner today may be updated more and may have the gear ratio option in it now. Apparently only one gear ratio came in the few diffs that were an option on them. Because the scanner would just ask if it was an 8-1/4 or 9-1/4 diff and so on it did not ask for actual gear ratio back when I was still at the dealer. You can call or stop at a local Mopar dealer and tell them what you did first and see what they say as like I said they may have more options today to set the specs in the ABS module. We usually called it setting the pinion factor. Thats because it was called that on front drive vehicles. Good luck , Ron