Towing Methods and Electrical Connections for an RV Towing a Car
Having a Vehicle at a Campground Gives You Flexibility
It is becoming more and more popular to take an automobile or other form of transportation with you when you use your RV on a trip, or even on a short vacation.
When you get to your destination, you can explore the surrounding areas in your towed vehicle.
The great thing about having a towed vehicle as you travel in your motorhome is that once you get to your campsite, you can park your RV, hook it up to the utilities, open the awning, and put out your chairs, tables, and grills, and you are ready for your overall camping experience.
And if you have a towed vehicle you can then explore the area surrounding your campground and enjoy the sights, people at your leisure.
Three Different Ways to Tow a Vehicle Behind Your Motorhome
The good thing for anyone who wish to tow a vehicle is that there are several ways to tow and each can use a different electrical hookup between the motorhome and the vehicle being towed.
Also, the towing capability of your motorhome and the kind of car you have will often help determine your choice of towing technology. You must know your rig's specs and weight limits before making a choice.
Method 1. Using a Tow-Bar Type Hitch
Towing your vehicle with all four tires on the road, sometimes called "towing 4-down," is usually the preferred method of towing another vehicle with your RV.
With this towing method you will have all four wheels of your towed vehicle, often called a TOAD on the road as you travel. This towing technique is by far the simplest way to hook up and unhook your automobile from your RV.
T tow a car this way, you utilize a ball hitch or single-point connection at the RV and a two-point connection system at the towed vehicle.
This connection and towing system allows your vehicle connection to swivel at the RV end and you also have two stable connections to the front of your towed vehicle, which provides a simple yet safe connection system.
Advantages and disadvantages of a Tow-Bar Hitch
- This is the most convenient system for RV drivers, as there is only one hitch or pivot-point connection, and the motorhome driver can actually back the RV up for a few feet with the car still hitched this way, when necessary. I have seen some old-timers actually back their 30+ foot long motorhome into a campsite with the tow car still hooked up. Personally, I don't have that skill, yet.
- After a long day of driving, when you finally get to your campground, you can easily and quickly disconnect your towed vehicle from your RV. and, the next morning's hookup is just as easy. This system requires the minimal physical exertion to connect or disconnect from your RV and should be seriously considered by any camper with physical limitations.
- Most automobiles are front-wheel drive, or all-wheel drive, and are not designed to roll down the road without the engine running and thus cooling the fluids in the transaxle. A few vehicles can handle this, but most manufacturers do not recommend it. You may end up with overheated fluids and seals, and possibly even permanent damage.
- Some front-wheel drive vehicles can be towed for several hours, either with the engine running (to keep fluid pumped to the axles) or with the RV driver stopping every 3-4 hours and running the engine for a few minutes to get the lubricants distributed properly.
- Some rear-wheel drive vehicles will require the installation of a solenoid switch kit which disconnects the axle in the vehicle in order to avoid similar damage to the transmission and rear-end.
- This type of towing, with some vehicles, requires that the vehicle have tow-bar adapters installed onto the front underside of the chassis for a safe connection to the tow-bar and thus to the RV. These adapters are usually designed to match the physical part of the specific automobile to be towed, so you must be sure that you install the right adapter.
Method 2. Using a Tow Dolly to Tow Your Vehicle
The Tow Dolly has been around for years, and it can be rented at almost all truck and car rental companies.
It is essentially a two-wheeled trailer, with a “ball hitch” adapter to mate to your RV.
You drive the front wheels of your car onto the trailer, and then you use the special straps and chains to tie the front wheels onto the trailer bed.
With this system, your front-wheel-drive vehicle's front end is stable on the tow dolly, and your rear wheels are free-wheeling as you go down the road.
Advantages and Disadvantages of a Tow Dolly
- You don't have to install any specialized tow-bar adapters or even wiring to your vehicle that will be towed.
- The tow dolly itself is relatively easy to hook up to an RV; that is if you are physically capable of lifting it and dragging it over to your RV to hook it up, and then crawl around on the ground to secure the towed vehicle to the Tow Dolly.
- The cost of a tow dolly is higher than the cost of the equipment used connecting the "toad" or "4-down" towing equipment.
- Backing up with a Tow Dolly attached is nearly impossible with this type of hitch. The pivot point is so short that the dolly/vehicle combination has an exaggerated response to turns when you try to back the RV up.
- Because you have two pivot points—the hitch point and the front axle of the car both turn—the car will often go in unpredictable directions when backing up. Almost everyone recommends that if you want to back up, you remove the car from the tow dolly, drive it out of the way, back up the RV/tow-dolly combination, pull to a safe place, and then reconnect the vehicle onto the tow dolly.
- The loading of the vehicle onto the tow dolly can easily take 20-30 minutes, and a good amount of sweat and physical dexterity as you crawl around under the vehicle and tow dolly tying things down.
Method 3. Using a Trailer to Tow Your Vehicle
You would not believe what I have seen going down the interstate highways on a trailer towed behind an RV.
Probably the most amazing combination to me was a double-decker trailer with a car on the bottom deck along with a motorcycle, a golf cart, and what looked like four bicycles strapped to the top deck.
How he got that golf cart up there and back down, I do not have a clue.
- You can get a trailer just about any size you desire, to carry any weight up to your RV's maximum limit.
- You do not have to make any mechanical or electrical modifications to your vehicle to tow it.
- Once you decide to use a trailer for your vehicle, you can then add other items that you want to use on your trip onto the trailer, along with the vehicle, and open up your limited RV storage areas.
- A lot of campgrounds do not have extra storage for trailers, and frown upon RVers who show up with a trailer that has to be stored.
- You can expect to pay an extra storage fee for your trailer at campgrounds.
You should always call ahead and plan your campground stops if you are towing a trailer, and check on their individual rules concerning trailers.
Picking the Right RV Towing Method
In summary, there are a number of requirements and options that you need to seriously consider when you decide to take a vehicle with you on your RV trip.
In addition to the information above, you need to do some research:
1. Research the popular brands of hitches that are available for your RV, and pick the one that you consider the best for you and your lifestyle and camping preferences.
2. Know your RV's exact towing capacity. Contact the manufacturer, or if they are not available, dig through your owner's manuals, and also check those labels that are glued all over the inside of your RV. In some cases they will list the specific towing data for your rig.
How to Tow a Car Behind an RV
How to Tow Your Car on a Tow Dolly
Towing a Car on a Trailer
Three Types of Electrical Connectors for Towing and How They Are Wired
With any of these methods of towing, you must have an electrical connection between the RV and the towed vehicle for lights, turn signals, brakes, and so on.
Pre-made cables are available at most camper part stores, as well as kits for wiring into the actual electrical harness of towed vehicles.
Coaches usually have a 6-pin or 7-pin connector mounted near the hitch itself.
Some of the wiring systems are simpler than others, but there are standards for the connectors and wiring.
Below is a short overview of the connections on the different popular electrical connectors.
1. The 4-Pin Towing Connector
The standard 4-pin tow connector is usually used for light towing. It is a flat plastic connector, with three pins either male or female, and the fourth pin the opposite sex.
The connector shown is for the wiring of the towing vehicle. The pins and their uses are listed below.
Function of Pins in 4-Pin Connector
Ground (male pin)
Tail lights, license plate light, side lights
Left turn and stop lights
Right turn and stop lights
2. The 6-Pin Towing Connector
The standard 6-pin tow connector is usually used for towing larger loads. It is a “keyed” round metal connector with the following connections.
The pins are shown from the wiring side of the towing vehicle's connector.
Functions of Pins in 6-Pin Connector
A (center pin)
red or black
TM (at the guide)
Left turn signal
Right turn signal
Electric brakes. This pin provides a variable voltage to the electric brakes of large tow trailers and campers to help stop them.
3. The 7-Pin Towing Connector
The standard 7-pin towing connector is used for towing large loads. It is a “keyed” round metal connector with the following connections, shown from the wiring side of the towing vehicle's connector.
Function of Pins in 7-Pin Towing Connector
Auxiliary power or backup lights (can be wired for either)
A Quality Electrical Power Adapter for Towing Vehicles
Once, when I had traded cars, I needed to connect my old camper and I purchased this kit. It was actually easy to install and worked great for me.
Renting a Car Versus Towing a Vehicle
Sometimes “the trip is not worth the tow.”. Or, in other words, especially if you are taking a short trip to one place and have no plans to run around a lot, you can just leave your car at home, and rent a car to get around. Or, if you don't plan on leaving the campground or camping resort very much, just take taxis when you need to.
I have done the math and even though towing is cheaper than renting a car (believe it or not) if you camp very often, it is a break-even situation if you just use a taxi a couple of times.
If you pack your RV carefully, and plan to stay in the campground or resort exclusively, then you don’t really need the hassle of the hookup, un-hooking, and towing.
In summary, consider what fits your lifestyle plans for your trip and stay. It is your choice to make and live with.
RV Towing and Safety Tips
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.
Questions & Answers
Right turn signal and brake light isn't working on the tow car, could this be a fuse problem?
More than likely its a connection problem with your tow cable on one end or the other. This especially so if your other tow car lights operate properly.
Look for oxidation on the contacts or loose connections.
© 2010 Don Bobbitt