2003 Toyota 4Runner Owners Manual - Page 1370

'03 4Runner_U (L/O 0305) 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 will most likely find stamped on the coupler are: Trailer class III and IV II I Typical trailer ball size 2 5/16 in. 2 in. 1 7/8 in. MATCHING TRAILER BALL HEIGHT TO TRAILER COUPLER HEIGHT No matter which class of tow hitch applies, for a safe trailer hookup, the trailer ball setup on must be the proper height for the coupler on the trailer. BRAKES AND SAFETY CHAINS D Toyota recommends trailers with brakes that conform to any applicable federal and state/provincial regulations. between the towing vehicle and the trailer. Leave sufficient slack in the chain for turns. The chain should cross under the trailer tongue to prevent the tongue from dropping to the ground in case it becomes damaged or separated. For correct safety chain procedures, follow the hitch or trailer manufacturer's recommendations. D A safety chain must always be used 2. Select the appropriate trailer ball to match or exceed the gross trailer weight rating of the trailer. The trailer ball load rating should be printed on the top of the ball. 3. When mounted in the ball mount, the threaded ball shank must protrude beyond the bottom of the lock washer and nut at least 2 threads. The trailer ball shank must be matched to the ball mount hole diameter size. NOTICE Only use a ball mount attachment specified for the Toyota 4runner. 1 Coupler 2 Trailer ball 3 Ball mount attachment 270 2003 4RUNNER from Apr. '03 Prod. (OM35820U)