Dodge Challenger 2010 Owner's Manual page 289

288 STARTING AND OPERATING
CAUTION!
Do not use two different size tires on the rear wheels,
as this can result in rear axle damage.
Tire Sizing Chart
Size Designation:
P = Passenger Car tire size based on U.S. design standards
....blank.... = Passenger Car tire based on European design standards
LT = Light Truck tire based on U.S. design standards
T = Temporary spare tire
31 = Overall diameter in inches (in)
215 = Section width in millimeters (mm)
65 = Aspect ratio in percent (%)
— Ratio of section height to section width of tire
10.5 = Section width in inches (in)
R = Construction code
— R means radial construction
TIRE SIZING TERMS