This increases the tire's footprint and allows the tire to perform as designed. Minimum operating pressure depends on tire size and rating and the weight on the tire. It is never below 12 psi for dual tires. Maximum pressure depends on tire size and rating. The outside tire pressure on duals should be about 2 psi lower than the inside tire pressure to reduce the chance of damage from the outer tire supporting the tractor.
Improper pressure can also decrease tire efficiency or cause damage to the tire.
Check the tables for maximum tire loads at various cold inflation pressures for bias and radial tires. Operate within the pressure range for the specified tire size and ply and do not exceed the maximum load. Air pressure also has a significant impact on tire life. If tires are continually operated at pressures below optimum, sidewall damage can occur, shortening their useful life. A recent survey by Farm Journal magazine found that 25 percent of tractor drive tires are underinflated by at least 2 psi.