1994 GMC Suburban Owner's Manual - Page 310

Special Tire Inflation 0 If you have 16 inch tires on your vehicle, and: - You'll be driving for very long at speedsof 66 mph (105 km/h) to 75 mph (120 km/h) where legal, inflate tires to 10 psi (70 kPa) more than the recommended cold inflation pressures. You'll be driving for very long at speeds of 76 mph (1 20 km/h) to 85 mph (135 k d h ) where legal, cold inflation pressures should be increased by 10 psi (70 kPa) and you must also reduce axleload capacity by 10%. Do not drive over 85 mph (135 km/h) even if it's legal. - Inflation pressures should never exceed 10 psi (70 kPa) above the inflation specified for the maximum load of the tire. Tire Inspection and Rotation To make your tires last longer, have them inspected and rotated at the mileages recommended in the Maintenance Schedule. See "Scheduled Maintenance Services" in the Index. n FRT FRT Use this rotation pattern. If your vehicle has fronttires with different load ratings or tread designs (such as all season vs. on/off road) than the reartires, don't rotate your tires front torear. After the tires have been rotated, adjust the front and rear inflation pressure as shown on the CertificatiodTire label. Make certain that all wheel nuts are properly tightened. See "Wheel Nut Torque" in the Index. 6-64