I bought 2 225/60/r16 all season tires at a very good price fpr my 2001 RX300 and put them on the front to replace the worn out 225/70/r16. So far I have not changed the rear tires, but there are warnings about mismatches on tire sizes. A friend said I could disengage the 4WD (rear axle) by a removing fuse labeled on FDW) I could find no such fuse and the owner's manual does not call out one. On this car is it a problem if I run the rear wheels larger (70 vs 60) n To disengage the rear wheel differential mechanically sounds dangerous given the function of the VSC (skid control) That light is on and has been on for quite some time and I have not had a problem with that.