Nihon Michelin Tire Co. Ltd. is adding studless winter tires to its full-refund satisfaction guarantee program. Four Michelin tire models – the X-Ice3+, X-Ice3, Latitude X-Ice2 and Agilis X-Ice – will be eligible for the program, which guarantees a refund of the full purchase price and installation cost if the customer reports dissatisfaction with tire performance within a 60-day return…