tow vehicle tire air pressure/load quandary
I have to replace tires on my Trailblazer soon, which I use to tow 5000 lbs (with no problems in over 25000 miles), with load leveling, anti-sway. The current tires are Toyo Open Country P245/65R17 w...
Forum Discussion
If you will allow me, I'll give some insight into what the vehicle manufacturer does regarding the pressure that is listed on the vehicle tire placard and in the owners manual.
Different vehicle manufacturers use different methods to arrive at the tire pressures, but once they get there, they select springs, shocks, and sway bars based on that pressure.
Then they test. They test the vehicle in all configurations - fully loaded, empty. If the owners manual calls for a different pressure when empty, they will have tested it.The handling tests are quite severe - commonly called limit handling.
So if your vehicle owners manual does NOT call for a different pressure when empty, the vehicle manufacturer probably did not test that condition.
We know that a tire's spring rate changes with pressure - and changing pressure that changes the handling balance - the understeer/oversteer characteristics.
I am of the opinion that the vehicle manufacturer's specifications should be followed because those conditions are known. Anything else is unknown.
Different vehicle manufacturers use different methods to arrive at the tire pressures, but once they get there, they select springs, shocks, and sway bars based on that pressure.
Then they test. They test the vehicle in all configurations - fully loaded, empty. If the owners manual calls for a different pressure when empty, they will have tested it.The handling tests are quite severe - commonly called limit handling.
So if your vehicle owners manual does NOT call for a different pressure when empty, the vehicle manufacturer probably did not test that condition.
We know that a tire's spring rate changes with pressure - and changing pressure that changes the handling balance - the understeer/oversteer characteristics.
I am of the opinion that the vehicle manufacturer's specifications should be followed because those conditions are known. Anything else is unknown.
