2003 Toyota Tundra Owners Manual - Page 212

'03 TUNDRA_U (L/O 0208) However, if towing with a fifth wheel trailer, the cargo load must be distributed so that the tongue load is 19 to 21% of the total trailer weight. Never load the trailer with more weight in the back than in the front. About 60% of the trailer load should be in the front half of the trailer and the remaining 40% in the rear. HITCHES D If you wish to install a trailer hitch, you should consult with your Toyota dealer. NOTICE Do not use axle-mounted hitches as they can cause damage to the axle housing, wheel bearings, wheels or tires. Also, never install a hitch which may interfere with the normal function of an Energy Absorbing Bumper, if so equipped. D Use only a hitch recommended by the hitch manufacturer and the one which conforms to the total trailer weight requirement. D The hitch must be bolted securely to the vehicle frame and installed according to the hitch manufacturer's instructions. D The hitch ball and king pin should have a light coat of grease. D Toyota recommends removing the trailer hitch whenever you are not towing a trailer to reduce the possibility of additional damage caused by the hitch if your vehicle is struck from behind. After removing the hitch, seal any mounting holes in the vehicle body to prevent entry of pollutants such as exhaust fumes, dirt, water, etc. 212 2003 MY TUNDRA (OM34419U)