I just got a '97 2500HD, ext-cab, long-bed, 6.5(F), auto, 4x4 and was told "OH! BTW, the rear axle had been swapped out, but the ratio was unknown and don't use 4 WD on hard pack , etc ...".
How do i find out what ratio it is? I can't see any tag mounted anywhere on the diff case.
Thanks for...