Ram Trucks 2015 Chassis Cab Commercial - Owner Manual - Manual (Page 386)

EXAMPLE:
65, 85, 80 = Aspect ratio in percent (%)
– Ratio of section height to section width of tire, or
10.5 = Section width in inches (in)
R = Construction code
– ЉRЉ means radial construction, or
– ЉDЉ means diagonal or bias construction
15, 16, 18 = Rim diameter in inches (in)
Service Description:
95 = Load Index
– A numerical code associated with the maximum load a tire can carry
384 STARTING AND OPERATING