Do Loaded Trailer Tires have Increase In Tire Pressure Compared to When Unloaded

Question:

Is the tire pressure supposed to measure with NO weight on the tire or under load? With 18,000# sitting on the tires there has to be a difference. Thanks

asked by: Rick

Expert Reply:

If the weight on a tire is heavy enough that the tire deforms then the pressure would increase with added weight. Under normal circumstances the pressure in a tire remains the same regardless if there is a load on them or not.

Since the volume of the tire does not change when under a load (only the shape) the pressure does not increase. In an extreme situation you may see an increase of around 1 psi.

So you will want to inflate the tires to their max psi rating when cold and you will be good to go.

expert reply by: Jameson C