Before you hit the road, take a look at these tips for loading towed vehicles. First, make sure you're not overloading. This may seem like common sense, but many forget about it. Check your vehicle's manual for weight capacity. After everything is loaded, you may want to make a stop at a public scale, especially when using a vehicle for the first time [source: Martin].
There are a lot of wrong ways to load cargo in a towed vehicle, so properly distributing items in tow will make a big difference. Top-heavy loads and loads that are focused too far to the front of the towed vehicle will cause it to dive when you brake and make the front wheels of the one you're driving lift off the ground. You can imagine how difficult it is to drive in that position. Conversely, when most of the weight is toward the back, this could lead to sway. Lopsided loads will also make it difficult to stay in control while driving.
Instead, distribute and spread out the weight of your load as much as possible to avoid dive and sway. Start with the heavy things on the bottom, and then place lighter things on top. This gives you a low center of gravity, making it more difficult for it to tip over. Experts recommend that you place about 12 to 15 percent of the total weight of the load on the hitch [source: Martin].If you're loading on a flat bed platform, keeping the load as low as possible will prevent the wind from affecting it when you're driving.
Of course, this strategic distribution won't matter much if the stuff won't stay where you put it. To counter the problems of inertia, you can use the principles of another physical force to your advantage -- friction. Gluing down rugs on the bed of your trailer adds friction so your items don't slide around [source: Martin]. Rugs certainly won't prevent it altogether, however, and they can hardly keep something from flying upward when you hit a bump in the road.
The best way to stop your box of special china from flying off a bed and tumbling into rubble is to tie it down. Your cargo will probably be pulled every which way during a rough ride, so account for every angle when you're strapping ropes around items. Make sure nothing is sticking out -- projections that protrude from an open trailer will be hazardous on the road, and many states have restrictions on them.
You've taken the time to thoughtfully load your towed vehicle and have finally made it to your destination without any disastrous loss of cargo. So it's time to relax, right? Wrong. Unloading takes both care and proper equipment. It would be a shame to go through all this trouble only to see things broken in the last phase.
The first step in unloading towed vehicles is to make sure you are parked on level ground [source: Carrabba]. If you must disconnect the towed vehicle on an incline, use blocks to stop it from rolling away. Ramps and dollies make it easier to unload heavy items. This makes sense in terms of physical forces as well, as ramps allow you to do the same amount of work using less force over a longer distance [source: Bloomfield]. When moving heavy items, make sure to move slowly to avoid damage and injury.
Safe towing involves not only following these tips for loading and unloading towed vehicle, but also using plain common sense, especially while driving. Learn more from the links below.
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More Great Links
- Bloomfield, Louis A. "How Things Work: The Physics of Everyday Life." 2nd Ed. John Wiley & Sons, Inc, New York: 2001
- Byrnes, Mike. "How to Prepare for the CDL." Barron's Educational Series, 2003. [Sept. 17, 2008] http://books.google.com/books?id=D7aSXfgOFEAC
- Carraba, Jim. "Trailer Safety Tips." NYCAMH/NEC. Country Folks Grower. June 5, 2006. [Sept. 17, 2008] http://www.nycamh.com/resources/safety_pubs/entry_detail.asp?article=58
- Land Transport NZ. "Loading and towing safely." Land Transport New Zealand. [Sept. 17, 2008] http://www.ltsa.govt.nz/road-user-safety/motorists/loading-towing-safely.html
- Martin, Joe. "Trailer Loading and Towing Guide." Sherline Products, Inc. [Sept. 17, 2008] http://www.sherline.com/lmbook.htm