Flat Tow Vehicle Setup – Roadmaster

California RV Specialists Is one of only a few qualified companies in the state that specialize in Recreational Vehicles Tow Bar Braking Systems. Flat Towing a vehicle behind your motorhome is a popular choice for transportation, below is some of the info you need to know to outfit your vehicle to your RV.


  • Base Plate – The tow bar is pinned into the receiver of the motorhome and connects to the base plate which is installed behind the bumper of the tow car.
  • Tow Bar – This connects the motorhome to the car.
  • Braking System – The law varies between states, but in California a braking system is required when towing a vehicle over 1500lbs.
  • Wire – The vehicle is wired to make the lights work in conjunction with the signaling of the motorhome.
  • Accessories – Essential products for flat towing.
  • Labor – It takes 16 -24 hours to install these items; our labor rate is $175 per hour.

RV Flat Tow Setup – Time Lapse


When considering a vehicle for towing behind your motorhome, always read the owner’s manual first – whether you already own the vehicle or plan to purchase it. It will provide valuable information on what is required before towing, which may influence your decision to use it as a dinghy. For example, some vehicles may require the removal of fuses, the disconnection of the negative battery cable and other steps, while others just require the transmission to be in neutral and the steering wheel unlocked.


The baseplate is the equivalent of a hitch receiver on a tow vehicle. First and foremost, make sure that a baseplate is available for the vehicle you plan to tow, and research what is involved with the installation.

Some baseplates bolt on easily with few modifications required, while others require the removal of the vehicle’s front fascia and/or modifications (read: cutting/trimming) to the grille, bumper mask, etc. Roadmaster all offer an extensive line of baseplates.


This style allows you to connect your tow bar directly to the baseplate, eliminating the need for a crossbar. This is our easiest system to connect and disconnect. If you are using a motorhome-mounted tow bar, this is the baseplate you should choose.


There is a wide selection of tow bars available from companies like Roadmaster and others, and features and functionality can vary greatly. Aside from the all-important weight rating, consider how the tow bar is stowed (on the vehicle or on the motorhome), and whether or not the bar is a non-binding or traditional design. Like the Roadmaster Nighthawk.

World’s first illuminated Towbar!


Permanent brake systems require a larger investment in time during the initial installation, especially those that leverage the air or hydraulic brakes in the motorhome to activate the brakes in the towed vehicle.

However, once installed, permanent systems require little more than plugging in the power cord and/or quick disconnect, and you’re ready to drive. Because a small control unit is all that is required, these systems are also hidden from view under the hood or in the passenger compartment.


Is recommended if you like convenience above all else and plan on keeping your towed vehicle for the foreseeable future. InvisiBrake is not a portable system, but the major components can be easily removed and installed in a new towed vehicle. InvisiBrake is the only ROADMASTER system that works with or without ‘active’ brakes right out of the box.


To tow your vehicle safely and legally, its running lights, turn signals and brakelights must mimic the motorhome’s. The most common ways to do this are with a wiring harness that plugs/splices into the dinghy’s taillights, or a “bulb-and-socket” system, so called because it bypasses the towed vehicle’s lighting with independent bulbs and sockets mounted inside the taillight assemblies. In either example, the wiring harness is routed to a receptacle mounted at the front of the vehicle, for connecting a cable to the motorhome.


These kits are for the most popular towing combinations kits. They include everything in the 154 above, plus a Flexo-Coil power cord, electrical socket and mounting bracket.


Some vehicles require the negative battery cable to be removed whenever the vehicle is flat-towed. The Roadmaster Battery Disconnect kit employs a solenoid that allows the user to disconnect the battery by simply pushing a button.


A Brake-Lite Relay stops the brake lights from functioning until the vehicle is started. This prevents the towed vehicle’s brake signal from overriding the motorhome’s turn signal.



If the brake lights do not work with the towed vehicle’s ignition key turned to the “tow” position, you need a brake light switch kit to provide a signal to the supplemental braking system. Roadmaster manufactures both vehicle-specific and universal brake light switch kits.


These simple charge line kits, easy-to-install kits help maintain the vehicle’s battery charge while in tow, supplying up to 15 amps of current. They also extend battery life by providing a constant maintenance charge (without overcharging)


Diodes are frequently used in wiring kits to prevent the backflow of current to the electrical system of the towed vehicle or motorhome; however, many newer vehicles now use a multiplex wiring system, whereby multiple electrical signals may be sent down a single wire (brake and taillights, for example).



Now that your dinghy vehicle has been completely outfitted, the next thing you’ll want to consider is how to protect it during travel. Every vehicle is exposed to some hazards during normal use, but when towed behind a motorhome, the risk of damage is magnified. Think about what would happen to your dinghy if your motorhome ran over gravel, tar or wet paint, and you’ll get the picture.


Is crafted from rotationally-molded, high-impact polyethylene to absorb the impact of rocks, gravel and road debris — instead of ricocheting it back at the motorhome. The Guardian can be attached and removed in seconds, and fits all ROADMASTER tow bars equipped with quick-disconnects.


Lastly demo and set up of the motorhome and tow vehicle. In some case the height between the motorhome and the tow vehicle can require a drop or rise shank. This helps to set the correct tow height between the two units.

We recommend that you take pictures and a video as a reminder during the demo.

We look forward to helping you get your vehicle safely setup for towing.

Safe Travels and Happy Camping, California RV Specialists.

More from Dustin

Dustin owns and operates California RV Specialists, an independent RV repair shop located in Lodi, CA. He thrives on sharing his knowledge and enthusiasm of RV repair and maintenance with his team, customers, and virtual friends.

Be sure to check out his YouTube channel, where he shares what’s going on in the shop and the product offerings in the store. Dustin is also very active on Facebook. Join his group, RV Repairs and Tips – What’s in the shop!

Dustin proudly operates the business alongside his wife, Ashley; but the true pair that run the show are their Boston Terriers, Arvie and Hitch.