2009 Toyota 4Runner Owners Manual - Page 248

2-5. Driving information n 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. Coupler Trailer ball n Before towing Check that the following conditions are met: l Ensure that your vehicle's tires are properly inflated. (→P. 479) l Trailer tires should be inflated according to the trailer manufacturer's recommendation. l All trailer lights work to be legal. l All lights work each time you connect them. l The trailer ball is set up at the proper height for the coupler on the trailer. l The vehicle remains level when a loaded or unloaded trailer is hitched. Do not drive if the vehicle is not level, and check for improper tongue load, overloading, worn suspension, or other possible causes. l The trailer cargo is securely loaded. l The rear view mirrors conform to all applicable federal, state/provincial or local regulations. If they do not, install rear view mirrors appropriate for towing purposes. 224