I have a 2007 GMC Yukon Denali with 20" alloy wheels. The chrome is peeling off and the alloy is corroding where the tire bead sits (in fact the wheels are corroding in a number of places). The tire size is P275/55R20 and the radius is approx. 31" The spare is a 17" steel with a tire size of P265/70R17. The radius is also approx. 31". Both tires have a circumference of approx. 97.4".
Is there any reason why I shouldn’t buy new 17" alloy wheels with tire size of P265/70R17? since that is what the stock tire are for this vehicle (The 20" rims were an option offered by GMC)?