Towing 4 Down vs. Dolly/Trailer

Many motor home owners tow their dinghy four wheels down or employ a dolly, two wheels down. The four down requires a mounting plate adaptor to be installed on the front of the vehicle.  This adaptor plate connects in two places to a tow bar that is attached to the motor home’s trailer hitch. The towed vehicle’s steering must be free of any locks so it can move freely. Due to the caster and camber designed into vehicle front ends, the towed vehicle will naturally follow the direction of the tow.   Connecting up and disconnecting is quite quick with this method and can be accomplished in minutes.

Towing with only two wheels on the road uses a short two wheel trailer called a dolly. The front wheels (in some few cases the rear) are driven onto the trailer and secured in place. The dolly, like any trailer, follows the tow vehicle.  It essentially is a four wheeled trailer with a longer than normal wheelbase.  Connecting up and disconnecting generally involves more work that a tow bar type tow. It takes about 10 minutes to complete.

So, which method is better?  Well, they each have advantages and drawbacks and much depends on your preferences.

There are a limited quantity of vehicle makes and models that are capable of towing on all four wheels. Generally this is due to the type of transmissions or presence of all wheel drive. In some cases there are non-approved makes that can be converted for this type of towing by the installing of a drive shaft disconnect device or a stand-alone transmission lubrication pump. This, of course, has a substantial cost and may void the auto’s warranty should a mechanical failure result.

There are two other issues that four down applications have to deal with. The set up does not permit backing up the RV/tow combination, save a straight 15 feet or so. Severe damage to the tow bar and/or adapting plate may occur.  Backing up cannot even be accomplished with a person steering the tow.  The other common problem is only experienced by high yearly tow mileage, not one trip to the south and back.  We are talking about towing four down 10,000 miles or so a year.  The tow vehicle’s tires suffer an abnormal wear pattern, generally referred to as “feathering”.  This is a result of “wheel barrowing” the tires; towing the auto without its tires experiencing any acceleration, braking, cornering torque, etc.  Tires are not designed for that application.  The more high performance type the tire, the worse this seems to happen.  It produces a slight, but annoying vibration when driving the vehicle.

With the tow dolly, backing is no problem as it handles just like any trailer.  Tire feathering seems no issue as this is more prevalent with the front tires.  The only two drawbacks to this method are storage needs for the dolly and the additional time required to load and unload.

Be aware, both methods require a braking system, but that’s a topic for a later discussion.

The choice is yours. Both can do the job!