High Pressure Tactics
Tire pressure is extremely important. It affects:
- Handling - Your vehicle will handle when your tires are properly inflated. Under-inflated tires result in a delayed response to steering.
- Tire Life - Both under and over-inflated tires will have a shorter lifespan than properly inflated tires. Over-inflated tires will have too much wear on the center of the tread and under-inflated tires will have too much pressure on the tire's side walls.
- Fuel Efficiency - The US Department of Energy claims that for every 1-psi drop in pressure, you can expect your gas mileage to lower by 0.4 percent.
- Ride Comfort - Lower tire pressure will result in a smoother ride but below the manufacturer's recommendation, will affect handling. High tire pressure will result in a more rigid and "loud" ride.
You probably knew all that but trucks and trailers are a little different than most passenger vehicles in that they typically require higher tire pressure. If you're a newb like we were you might be surprised to hear that your truck and trailer tires might require pressures as high as 80 PSI. Tires carrying heavier loads require higher tire pressure.
What is the correct pressure?
Something you might not know is that you can't always rely on the printed PSI guidelines on your tire for the proper pressure. Each tire has an acceptable range but the manufacturer doesn't know what you're using the tire for. Your vehicle should have the pressure listed in the owner's manual as well as on the tag attached to the vehicle door edge, doorpost, glove box door or fuel door. Your trailer's owner's manual should also contain the appropriate pressure for the tires on the trailer.
Keep in mind that the listed pressures are "cold" pressures meaning that they are the pressure your tires should be when the vehicle hasn't been driven for 3 hours. Driving causes your tires to heat up which causes air to expand and tire pressures to rise. A "cold" 80 PSI tire can easily reach 90 PSI when driving for an hour or two in warm weather conditions.
How/where can I fill my tires?
Something else we didn't know was that not all air compressors are created equal. I think we blew about $6 in quarters before we realized that the local gas station's air compressor wasn't going to get our trailer's tires up to 65 PSI. There are usually two guaranteed options.
- Truck stop: Truck stops have air compressors intended for heavier vehicle, higher pressure tires.
- Your own portable air compressor: We don't recommend buying a 12v cigarette lighter air compressor as we did because they're typically not intended for the high pressures required by trucks and trailers and will likely burn out quickly. We bought a portable, Dewalt cordless air compressor capable of 135 PSI. It cost a pretty penny and I wouldn't recommend it for just putting air in your tires. We also bought it for pneumatic tools we used for renovation projects. If you do get yourself a compressor make sure to get yourself an inflator and gauge. We bout a JACO FlowPro and are very happy with it.