1999 Lexus LX 470 Owners Manual - Page 405

"Total trailer weight "Tongue load Hitches D If you wish to install a trailer hitch, please consult your Lexus dealer regarding the weight distribution capabilities of the hitch. D Use only a hitch which is recommended by Lexus dealer and 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 The trailer cargo load should be distributed so that the tongue load is 9 to 11 % for weight carrying hitch (*1) or 15 % for weight distributing hitch (*2) of the total trailer weight, not exceeding the maximum load of the following. Tongue load x100 = 9 to 11% (*1) or 15% (*2) Total trailer weight Weight distributing hitch Weight carrying hitch 442 kg (975 lb.) 295 kg (650 lb.) D 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. Trailer ball Follow these easy steps to properly determine the correct trailer ball for your application: 1. Determine the correct trailer ball size for the trailer coupler. Most couplers are stamped with the required trailer ball size. The sizes you'll most likely find stamped on the coupler are: Trailer Class III II I Typical Trailer Ball Size 2-5/16 in. 2 in. 1-7/8 in.