Common 5th Wheel Trailer Problems & Issuesby Richard Rowe
Fifth-wheel trailers certainly do have their benefits, and are in most ways superior to bumper-mount trailers. A fifth-wheel mount can take more weight, can contribute stability to the tow vehicle by evenly distributing weight and can make for easier and quicker parking and backing. However, fifth-wheel trailers aren't free of their issues; few are insurmountable, but they all warrant attention.
Front Suspension Loading
The fifth-wheel arrangement's primary asset is also its Achilles' heel where some vehicles are concerned. FW-equipped vehicles can tow heavier loads than those with bumper mounts because they place the weight of the trailer directly over the rear axle instead of behind it. In essence, the trailer presses straight down on the tow vehicle's suspension instead of levering the front wheels upward. This isn't usually a bad thing, except that 20 percent or more of the trailer's weight can end up borne by the front axle. In most cases this will actually enhance the tow vehicle's stability, but bear in mind that the front springs and suspension usually aren't designed to accommodate such a load.
A fifth-wheel trailer by nature offers more turning angle than a bumper-mount trailer, but the consequences of a mistake can be much greater with a fifth-wheel. Jack-knifing a bumper-mount trailer during backing and parking maneuvers will send the trailer into the corner of your vehicle, where it'll likely crack and stop on the tail-light before causing any real damage to the truck's sheetmetal. Turning a fifth wheel to its extremes will land the side of your trailer right in the corner of your truck cab, which is far more expensive to repair. And the truck cab is far stronger than your tail-light, which means probable damage to the trailer.
Cost and Quality
Consumer-grade trucks capable of pulling a fifth-wheel trailer have proliferated through today's market, due in part to current manufacturing trend but also to those of a decade ago. Used trucks have put huge towing power into the hands of people who can't necessarily afford a quality-built $40,000 trailer. This has created an expanding market of sub-par trailers that wouldn't sell for half of what a quality trailer would. You definitely get what you pay for where luxury items like this are concerned, which makes rapid trailer deterioration a serious problem for pull-behind RV buyers. If you're in the market for a luxury trailer, you're probably better off buying a used name-brand unit than a brand-new one of the same cost.
Size, Weight and Cost
Fifth-wheel trailers are expensive, and in a way, that's a good thing. Typically, those who can afford an expensive and heavy fifth-wheel have already done their homework and bought a truck capable of safely pulling it. Of course, that isn't always true; in general, you'll want a truck that weighs at least 25 percent of the total vehicle weight including the trailer. Any less than that and you could wind up with a trailer that drives the truck instead of a truck pulling a trailer. In terms of wheelbase, longer is better for high-speed stability and shorter wheelbases make for easier parking. For around-town use, you'll want to keep the distance from the kingpin to trailer axle the same or shorter than the truck's wheelbase. Any longer and you'll end up hopping curbs all the time.
Richard Rowe has been writing professionally since 2007, specializing in automotive topics. He has worked as a tractor-trailer driver and mechanic, a rigger at a fire engine factory and as a race-car driver and builder. Rowe studied engineering, philosophy and American literature at Central Florida Community College.