A previous thread on this subject claimed aluminum foil under the tires worked and make sure no other connection, hoses, power cords, etc touch ground. I did it two years and no mice. I have now taken it one step farther. I put aluminum flashing which I wax with auto wax first, under the tires. Three years now no mice. Seems the slick surface does not give them traction to climb up the tires. I also put the vinyl wheel covers on and even before I used the foil/flashing noticed a reduction in mice even though that left part of the tire unprotected. Traps around the tires also help