Dually truck tire replacement
Have an F350 dually with tire size LT 245/75R17 121/118R Obviously I need same diameter. Wonder how important aspect ratio is to match current tires (original are Yokohama tires)
Forum Discussion
Aspect ratio? As in the "75" in that tire size?
That is pretty important. It IS the tire height.
245=tread width in mm
75=sidewall height as a % of tread width. ex: 245 x 0.75=183.75mm
17=rim diameter in inches
So...
total sidewall height in mm = 183.75*2=367.5
total sidewall height in inches = 367.5/25.4=14.47 inches
total diameter = 14.47+17 = 31.47 inches
Of course, there are discrepancies from tire to tire and manufacturer to manufacturer. But that is what the numbers are suppose to mean.
That is pretty important. It IS the tire height.
245=tread width in mm
75=sidewall height as a % of tread width. ex: 245 x 0.75=183.75mm
17=rim diameter in inches
So...
total sidewall height in mm = 183.75*2=367.5
total sidewall height in inches = 367.5/25.4=14.47 inches
total diameter = 14.47+17 = 31.47 inches
Of course, there are discrepancies from tire to tire and manufacturer to manufacturer. But that is what the numbers are suppose to mean.
