i think that any difference in tire size is going to mess up the TOD, where are the larger tires? the larger tires should be moved to the front so the tod computer doesnt think the wheels are spinning faster than the rears.. i think this is only a partial fix, and to fully fix the problem you will need all 4 tires to be the same size.. once everything is evened out, i think resetting the computer (disconnect battery for about an hour) should fix the TOD if its just the tires causing it

im no expert, this is just what ive picked up through various other threads and my own personal experience with 2 worn/2 new tires on the vx