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dale farley
03-28-2013, 10:14 AM
Discover the benefits and equipment necessary to tow a vehicle four wheels down behind a motorhome.

This is the first of a two part series on the basis of towing. Although it covers basic information, it gives some valuable tips that you may not have thought about and reinforces those things we tend to take for granted. The second part of this series will list several manufacturers and models of Tow Bars and Base Plates currently avalialbe.

By Jim Brightly
Modified for inclusion in POG forum.

Anyone who has toured fantastic Yellowstone National Park in a 38-45 foot, wide-body motorhome on the park’s narrow, highly crowned roads understands how difficult and exhausting this type of driving can be. The same goes for anyone who has driven through Los Angeles or New York City, or has tried to find their heart in San Francisco while negotiating its tight streets and steep hills in a full-size motorhome. Leaving the motorhome in a safe harbor and driving a smaller vehicle is more fun, less stressful, more economical, and safer, especially when trying to get through rush-hour traffic or navigate winding mountain roads.

That’s why so many people choose to tow another vehicle behind their motorhome when traveling. A towed vehicle (also called a towable, a toad, or a dinghy) can vary in size from a compact car to a large sport-utility vehicle, with some folks even towing full-size pickups. A towed vehicle provides convenient transportation after arriving at a destination in a motorhome. Let’s face it; after finding a campsite, positioning and leveling the motorhome, and hooking up the shore connections, who wants to break camp just to make a trip to the store or the museum a few miles away?

Motorhome owners have three options when it comes to towing a second vehicle: on a trailer with all four wheels off the ground; via tow dolly with the drive wheels off the ground and the rear wheels on the ground; or flat towing with all four wheels on the ground. Which towing method you choose often will be determined by the vehicle you wish to tow.

All vehicles can be towed on a trailer, making it the most versatile of the three options. Because all four wheels of the towed vehicle are off the ground, this method does not require the installation of additional equipment or necessitate any special procedures. The major drawbacks with a trailer are the additional weight and finding a place to store it once you reach the campground.

A tow dolly can be used for most two-wheel-drive vehicles in which the rear wheels are not part of the power train. As with the trailer, a vehicle being towed on a dolly does not require the installation of additional equipment, but the owners manual may include special instructions that should be followed before it is towed. Once you reach your destination, you will have to find a place to store the dolly, but because it is smaller than a trailer, it is less of an issue.

Flat towing, or four-wheels-down towing, is the most popular method of towing among motorhome owners, because of its simplicity and convenience. This type of towing requires the installation of a base plate on the towed vehicle and the use of a tow bar that links the motorhome and the towed vehicle. Because all four wheels travel on the ground, the automobile manufacturers approve only certain vehicles to be towed in this manner, and each vehicle will include special instructions and procedures that must be followed before, during, and after towing. The most significant benefit of flat towing is that once a destination is reached, it takes little time to disconnect the towed vehicle from the motorhome, and, other than the tow bar itself, there is nothing to store.

The towing method(s) approved by the manufacturer for a particular vehicle are typically detailed in the vehicle’s owners manual under a heading such as “Recreational Towing.” Whether you already own a vehicle you would like to tow or are looking to purchase a new or preowned vehicle to tow, always check the owners manual to determine how it can be towed.

The Art Of Towing
Fortunately, it doesn’t take much effort or equipment to turn a motorhome into an efficient towing vehicle, as most are equipped with a receiver hitch and a taillight connector at the factory. However, a bit more effort must go into prepping a vehicle to be towed. While there are several things to consider when towing by any method, the following two items are very important when it comes to safety.

1. Do not exceed the motorhome’s gross combination weight rating (GCWR) — the combined weight of the motorhome, the towed vehicle, and their contents.

2. The motorhome’s gross vehicle weight rating (GVWR) — rather than the GCWR — is the key figure when considering the need for a supplemental brake system. The GCWR should be used when considering the total weight to be moved forward under the motorhome’s power. You must use the motorhome’s GVWR — the maximum allowable weight — for braking purposes. A motorhome’s service brakes are designed for its GVWR, not its GCWR. Many motorhome manufacturers recommend the installation of a supplemental brake control system to activate the brakes on a vehicle, dolly, or trailer that is being towed. It’s been discussed many times in the pages of Family Motor Coaching that the physics of weight enter the picture when you’re towing, and you need the additional safety and peace of mind that supplemental braking gives you. Many of the supplemental brake systems include a breakaway safety device that will activate the towable’s own service brakes should the motorhome and the towable become separated.

During the process of connecting the towed vehicle, dolly, or trailer to the motorhome, never allow yourself to be distracted. Use a checklist if you need it. I’ve found that a laminated list and a dry-erase marker work the best. If you do become distracted before the hookup is completed, start over. After all, if you’ve forgotten something and your towed vehicle, dolly, or trailer breaks free, the result could be catastrophic. My suggestion is to get into a daily (or departure) routine. If you hook up the towed vehicle, including coupler, safety chains/cables, lights, etc. the same way each time, it becomes second nature. Before buckling in to drive away, always do a final walk around. Make sure all the lights work properly, no trash or equipment is left lying around, and the towed vehicle is properly set up for towing.

When hooking up the safety chains (or cables), make sure to cross them under the coupler between the tow bar or dolly/trailer tongue and the receiver. This method offers two safety improvements over simply attaching the chains in parallel. Should the coupler become disconnected from the hitch, the crossed chains will not only support the coupler/tow bar, but they also tend to hold the towed vehicle, dolly, or trailer in a straight line behind the motorhome. Safety chains connected to the motorhome in parallel will allow the coupler/tow bar to fall down to the pavement and the towed vehicle to wander back and forth to the limit of the chains, which could cause severe damage to both vehicles

Flat-Towing Equipment
The tow bar assembly transports vehicles with all four wheels touching the ground. In general, flat towing is the easiest and the least expensive towing method. Most tow bars are rated from 3,500 pounds to 5,000 pounds, with a few offerings that are rated up to 10,500 pounds (or even higher). The system usually consists of two elements: the tow bar (or wishbone portion) that connects the motorhome and towed vehicle, and the base plate, which attaches to the chassis of the towed vehicle. The tow bar is more generic, while the base plate is designed and made for a particular vehicle or a chassis that is used on a number of models. The base plate provides a secure point of attachment for the tow bar.

Many tow bar manufacturers offer motorhome-mounted tow bars that remain attached to the motorhome and connect to the towed vehicle’s base plate only when the car is being pulled. This type of tow bar offers the advantage of a built-in storage location (on the back of the motorhome) and a cleaner-looking towed vehicle. They also have the advantage of applying their weight to the rear of the motorhome instead of to the front of the towable. Folding models that can be flipped and stowed horizontally or vertically on the base plate of the towed vehicle also are available.

While flat towing with a tow bar is favored by many motorhome owners, there are some disadvantages to this method. First, tow bar base plates tend to be unique to a particular model, and if a base plate does not exist for your vehicle, a custom-made installation can be expensive. During flat towing, some portions of the towed vehicle’s drivetrain (tires, wheel bearings, driveshaft components, etc.) will undergo wear and tear. Plus, many vehicles cannot be towed in this manner without drivetrain modification. Remco Manufacturing produces a lube pump that will continuously lubricate the transmission’s inner gears while the vehicle is being towed. Remco officials can tell you whether your vehicle can be towed four wheels down without modification and, if not, whether the company has a lube pump that will work on your vehicle.

With virtually all tow bar systems, the motorhome cannot be backed up when the towed vehicle is attached. Almost every time a flat-towed vehicle is backed, even with an assistant driver attempting to control the towed vehicle’s steering wheel, its front wheels will try to crank to their stops on one side or the other — sometimes resulting in injury to the person holding the steering wheel. This is caused by the caster angle in the front end of the towed vehicle. To be on the safe side, don’t back up with any tow bar.

Bill Dator
03-28-2013, 08:14 PM
Great article. Having a checklist and following it is good advice. I hooked up in Cheyanne Wyoming and when I got to Denver I realized that I left the emergency brake on. My wife still tells people that we had a strange smell caused by towing her car.