Truck Tire Pressure Guide
Why pressure matters
Truck tires carry high loads over long distances. Small pressure errors can create heat, uneven wear, and poor handling. The correct setting depends on axle load, tire rating, road speed, and temperature. A fixed number is often too simple for mixed freight work.
Load and inflation
A tire supports weight because air pressure pushes against the casing. More load usually needs more cold inflation pressure. This calculator uses a linear load ratio. It compares the adjusted tire load with the rated tire load. The rated pressure then scales with that ratio. Real tire makers publish load-inflation tables. Those tables should guide final service settings.
Axle sharing
Axle weight is not always shared perfectly. Road crown, cargo position, suspension condition, and dual tire mismatch can place more load on one tire. The imbalance field raises the load for the heaviest tire estimate. This gives a safer planning number when exact wheel scales are not available.
Temperature effect
Pressure changes as air temperature changes. A tire checked in a hot yard may show more pressure than the same tire on a cold morning. The calculator adjusts the set pressure with an absolute temperature relationship. This helps match a desired cold pressure at a reference temperature.
Speed and reserve
Higher speed can add heat and stress. The speed factor adds a modest allowance. The reserve margin adds another buffer for small weighing errors and gauge variation. Do not use reserve margin to exceed the tire rating. If the result is near the rating, reduce load or choose a stronger tire.
Service checks
Check tires when they are cold whenever possible. Use an accurate gauge. Inspect valve stems, tread, sidewalls, and dual spacing. Compare steer, drive, and trailer axles separately. Record results for repeat routes. Good records make fleet pressure decisions easier. They also help detect slow leaks before failure.
Important note
This tool is an estimator. It cannot replace tire maker data, vehicle placards, or legal inspection rules. Always confirm the final inflation value with official service information.