By Ken Freund
March 3, 2017
Filed under RV Tech Q&A
What small car is best to tow behind a 24-foot Thor Citation with a Mercedes diesel? Are front-wheel-drive (FWD) or all-wheel-drive (AWD) cars OK? And, which is easier to hook up and unhook: a tow hitch or a dolly?
Howard Husselman | Horse Shoe, North Carolina
There is no one “best” small car for towing, as each has its pros and cons, and these factors vary for different people. For example, someone very tall might consider legroom as a top consideration, while someone else might favor cargo space or off-road ability or powertrain type. In general, the lighter the vehicle, the better it will be for towing behind your motorhome. Be sure to stay within the manufacturer’s weight limitations.
While most owners probably agree that a tow bar is easier to hook up and use than a tow dolly, tow dollies (or trailers) are necessary for vehicles that were not designed to be towed on all four wheels. While many FWD vehicles with manual transmissions are towable, many FWD automatics and most AWD vehicles are not towable as produced by the factory. You need to carefully read MotorHome’s annual Guide to Dinghy Towing, which lists vehicles approved by their manufacturers for towing along with answering many other questions, and it is also available on our website at www.motorhome.com.
We just bought a 2017 Forester 3011DS, with a Ford E-450 chassis and a V-10 engine, that has less than 1,000 miles on it. It’s new from a dealer and I hear a rumbling sound when going 45 mph or more. At first it seemed like it did it mostly when I was pressing on the gas to go uphill. Now it is also doing it when I let off the gas. Have you heard of this problem before?
Allan Blair | Fredericksburg, Virginia
Chances are that it’s a normal sound, and you may not be familiar with the new motorhome and the noises it makes. However, because things can go wrong, it’s always good to check it out. Motorhomes are generally a lot noisier than passenger vehicles when they’re going down the road. Without my being able to hear it, and not knowing even what area of the vehicle the noise is coming from, it’s pretty much impossible to diagnose by email. I recommend that you take it to the dealer and have someone test drive it with you, so that you can determine what the noise you’re hearing is. My best guess is exhaust noise. I’d like to hear back from you after it’s diagnosed.
Equalizer Hitches on Motorhomes
I’m a snowbird who lives year-round in my RV, which is a 2006 Winnebago Minnie 31C Class C motorhome. It’s on the 2005 Ford E-450 chassis, with the V-10 engine. It has standard suspension (no air shocks).
The owner’s manual states: CAUTION! Do not install a frame equalizing type hitch on your vehicle. Max. hitch pulling capacity: 5,000 lbs. Max. tongue weight: 350 lbs.
I have a 12-foot-long Cargo Mate two-axle cargo trailer that I used last year to transport my motorcycle. The trailer, fully loaded, has been weighed and is not overloaded (3,850 pounds). I have inquired about this at three different Ford dealers, a Camping World and several independent hitch-installation shops. None of them had an explanation for not using an equalizing hitch on my motorhome. I used an equalizing hitch to tow this trailer last year, with no mechanical towing problems. Without the equalizer hitch the rear of the motorhome goes down about 2 inches. The only problem I had was the electric trailer brake was wired wrong. I’m still trying to find the correct wire for the electric brake. Winnebago only uses two colors of wires from the cab, yellow for positive and white for negative. At the rear of the RV, there are about eight yellow wires and one white wire.
Ray Russell | Yuma, Arizona
Equalizer-hitch installations create torque loads that are fed into the towing vehicle (upward loads) that are considerably stronger than those generated by a weight-carrying hitch. Additionally, the equalizer hitches place rotational torquing loads on the receiver and frame rails, etc. It must be understood that the frame rails on a chassis are not the only components carrying trailer hitch loads. In a motorhome of the type you have, the floor, back wall, side walls and roof all share parts of the stress because of unitized construction. These stresses are the engineer’s concern with an equalizer hitch, which may exceed the design’s structural limits under certain operating conditions, and one that the average technician or dealer probably wouldn’t be knowledgeable or concerned about. If the loaded trailer actually weighs 3,850 pounds, and hitch weight should be about 10 percent of that, or 385 pounds, you are slightly above the factory-recommended limit of 350 pounds. By culling out a few items, you should be able to bring the weight down to within limits. You might need to store something heavy in a storage compartment, etc. However, don’t move the heavy stuff to the back of the trailer to reduce hitch weight; this could cause a dangerous sway condition. Air bags could be used to bring the rear of the motorhome back up to level instead of using the equalizer-hitch function.