2009 Jeep Liberty Owner's Manual - Page 351

STARTING AND OPERATING 349 Tire pressure may increase from 2 to 6 psi (13 to 40 kPa) during operation. DO NOT reduce this normal pressure build-up, or your tire pressure will be too low. 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 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 and cold tire inflation pressures. WARNING! High speed driving with your vehicle at or above maximum load is dangerous. The added strain on your tires could cause them to fail. You could have a serious accident. Do not drive a vehicle loaded to the maximum capacity at continuous speeds above 75 mph (120 km/h). Radial-Ply Tires 5 WARNING! Combining radial ply tires with other types of tires on your vehicle will cause your vehicle to handle poorly. The instability could cause an accident. Always use radial tires in sets of four. Never combine them with other types of tires.