Tire tools

What every number in 11R22.5, 295/75R22.5, 18.4-38, 23.5-25 or 21x7x15 means, with diameter and revolutions per mile.

Changing tractor tires? Pick current and new sizes and see how front axle lead changes — 150+ farm sizes, no gear ratio needed.

11R22.5 vs 295/75R22.5 and 30 more sizes: diameter, revolutions per mile, speedometer and engine RPM change, load ranges.

What G, H, L and 146/143 mean, in lbs and kg.

18.4-38 = 480/80R38: metric equivalents and same-height options for farm tires.

Last 4 digits of the DOT code → week and year made, and how old the tire is.

Press-on 21x7x15, pneumatic 6.50-10: real dimensions, load and the diameter at which to replace.

Axle weight → minimum cold pressure for single or dual tires.

Front weight and rear implement → axle loads and load per tire.

Gallons and added weight at 75% fill — water or calcium chloride, 226 sizes.