There are several different...
There are several different and accepted methods to join a tow vehicle and trailer, each one with its own advantages and drawbacks. By far the most common for recreational use is the ball and coupler setup, available in 1 7/8-, 2- and 2 5/16-inch sizes. Why anybody uses the 1 7/8 stuff we'll never understand, but many a trailer has been lost because of a 1 7/8-inch ball in a 2-inch coupler. If you don't do anything else right when hitching a trailer to a tow vehicle, at least use parts that are made to work together.
Whether it's a covered trailer or a flatbed with trail toys, a small home on wheels, or some combination thereof, towing is more popular than ever with the four-wheeling crowd. That the available tow vehicles are far more capable than in the past has certainly helped put more trailers on the road, but may also have contributed to putting a lot of trailers off the road. And not on purpose, at some nice campsite. A powerful engine and well engineered chassis can take much of the difficulty out of towing, making life easier for a conscientious trailer puller. On the other hand, the tow vehicle's improved performance can just as easily get the unwary in deep trouble.
Towing a trailer is much like driving a car in the first place. It's a responsibility not to be taken too lightly. Towing just makes the responsibility longer and heavier, and harder to stop and maneuver. Unfortunately, many don't give the issue much more thought than, "If the trailer fits, tow it." Sometimes, not even that much. Trailer towing is one of the better indications that there indeed may be a higher power that protects the truly ignorant. True, there are a lot of crashed and broken-down trailers along the sides of the nation's highways on any given day, but nowhere near as many as one would expect when considering how often no common sense at all is applied to trailering.
For example, when you see a lifted pickup towing a heavy trailer, speeding down the road with the headlights pointing towards the sky because of a weak rear suspension and/or excessive tongue weight, it isn't an "accident" waiting to happen. By definition, accidents aren't planned, so it's more of a trying-to-beat-the-odds situation when towing with an improper setup. Speeding doesn't exactly help. Towing without trailer brakes, towing more than the vehicle can rightfully handle, having the wrong tongue weight, or not using safety chains are all things that can easily cut a trip short-even if nothing unexpected takes place right in front of you. While we're definitely in favor of improving the gene pool, the highway system isn't the best place to gamble, as there are plenty of innocent people using the roads, and they shouldn't have to suffer from somebody else's stupidity. Besides, we would like at least some of those trailering yahoos to survive, grow up, and eventually become Four Wheeler readers.
Perhaps the most overlooked aspect of trailering is tongue weight, yet that's something which can make the difference between a trailer that tows like a dream and one that won't stay in the lane. Or even on the road.
It's often a legal requirement...
It's often a legal requirement to have two safety chains, except on fifth-wheel trailers, and they should run crosswise between the tower and towee. That way, should something in the connection fail, the trailer is limited as to how much it can sway and move in general, making it feasible to come to a safe stop. With some luck, the coupler may not even hit the ground and get ruined. In California, the chains can't legally be any longer than necessary for making tight turns, and open hooks aren't allowed. Improperly secured hitch pins and worn-out couplers seem to be the most common causes for the safety chains having to take over.
The location of the axles in relation to the length of the trailer and the placement of the load determines the amount of the load that the trailer puts on the tow vehicle. This is why they're called "semi trailers"-they don't carry all of their own weight, which is why it's so important to get the tongue weight right. So-called "full trailers," which are quite rare, have at least one axle at each end, and only part of the weight of the drawbar is supported by the tow vehicle. This makes full trailers immune to tongue weight issues, just as with flat towing.
Gooseneck and fifth-wheel trailers usually don't have tongue weight problems, assuming a correctly positioned hitch and appropriate trailer weight, since the weight is applied slightly ahead of the rear axle. It's when using a receiver or bumper-mounted setup, positioned at the far rear of the vehicle, that tongue weight becomes critical-and this is how the majority of four-wheeler's trailers are towed.
Too much tongue weight makes the front of the tow vehicle too light, hurting both steering and stopping performance because the front tires no longer have enough contact pressure to work properly. In the process, the rear axle and tires may become overloaded-plus, it even looks pretty darn dumb when going down the road with headlights facing the stars. While harder to see, perhaps, not enough tongue weight can be even worse, allowing the trailer to push the rear of the tow vehicle around. As a rule, 10 to 15 percent of the trailer's total weight should be applied to the tow vehicle, leaving the trailer carrying the remaining 85 to 90 percent.
So how do you find the correct tongue weight? There are special scales made for the purpose, such as the ones by Sherline Products, and most outfits that make towing hardware-Valley Industries, for example-have catalog illustrations showing how to use boards, pipes, and a bathroom scale to measure tongue weight. Either way, you must first weigh the trailer at a scale to find out what the gross trailer weight is, loaded up with everything you will have on it, to know what tongue weight to shoot for. If you always use the same trailer with the same load, such as your trail vehicle, you can use trial (and hopefully not much error) to find where to tie the four-wheeler down for the best handling. Then mark that position on the trailer for future reference.
 Incorrect tongue weight is...  Incorrect tongue weight is the cause of hundreds of trailer crashes every year. Getting it right can be done using common sense and experimentation, but a safer, faster method is to actually weigh the tongue with a scale. This hydraulic Sherline Products unit comes in 1,000-, 2,000-, and 5,000-pound versions and includes a threaded "peg" to fit in a coupler. |  Sometimes you gotta do what...  Sometimes you gotta do what you gotta do. This contraption uses seven hitch pins, a homemade riser of sorts and an upside-down pintle hook. It's not the safest setup we've ever used, but that's what it took to make it possible to move an 18-foot-long load on an 8-foot trailer-very slowly, on private property. |  Towing doesn't necessarily...  Towing doesn't necessarily require having the balls to do it. Pintle hooks are stronger and inherently more foolproof than trailer balls and couplers. There's no mistaking a 1 7/8- and a 2-inch ball with a pintle setup. There are several sizes of hooks and lunette rings, but either the lunette fits in the pintle or it doesn't. Pintle hooks are always bolted to something, while lunettes can be welded or bolted on. Some feel that a pintle setup is noisy, but with the correct parts and tongue weight, it shouldn't be. |
When the correct tongue weight turns out to be more than the tow vehicle can handle, or is rated as dead weight, it's time to get a weight-distributing hitch. Using trailer-mounted spring bars that in effect shift weight from the rear to the front of the tow vehicle makes it possible to tune the setup to perfection. Another worthwhile trailer accessory could be a sway control, which can do wonders for stability and is usually an option with weight-distributing hitches.
Yes, it can take some work and cost some money to get the tongue weight right, but that's the price you pay for pulling a semi. When it's correct, the reward is, as the say, priceless.