2010 Jeep Wrangler Owner's Manual - Page 401

400 STARTING AND OPERATING speeds, maintaining correct tire inflation pressure is very important. Increased tire pressure and reduced vehicle loading may be required for high-speed vehicle operation. Refer to original equipment or an authorized tire dealer for recommended safe operating speeds, loading Example: If garage temperature = 68° F (20° C) and the and cold tire inflation pressures. outside temperature = 32° F (0° C) then the cold tire inflation pressure should be increased by 3 psi (21 kPa), WARNING! which equals 1 psi (7 kPa) for every 12° F (7° C) for this outside temperature condition. High speed driving with your vehicle under load is dangerous. The added strain on your tires could Tire pressure may increase from 2 to 6 psi (13 to 40 kPa) cause them to fail. You could have a serious accident. during operation. DO NOT reduce this normal pressure Do not drive a vehicle loaded to maximum capacity at buildup or your tire pressure will be too low. continuous speeds above 75 mph (120 km/h). Tire Pressures for High-Speed Operation The manufacturer advocates driving at safe speeds within posted speed limits. Where speed limits or conditions are such that the vehicle can be driven at high Tire pressures change by approximately 1 psi (7 kPa) per 12° F (7° C) of air temperature change. Keep this in mind when checking tire pressure inside a garage, especially in the Winter.