How to Tow a Car Behind an RV – Dinghy Towing

Learning how to tow a car behind an RV can be a bit overwhelming. There are multiple ways to tow and once you figure out which way you want to tow, there are still pieces of the puzzle to put together.

However, once you figure out the initial setup, bringing your favorite vehicle along with you takes a matter of minutes.

3 Main methods for towing exist. Those include a (1) trailer, (2) dolly, and (3) dinghy towing.  Out of the 3, I would recommend dinghy (4 down) towing for your towed vehicle. If you already own a trailer or a dolly, those could be options, but if you are starting from scratch, I would definitely tow 4 down.

A trailer adds a lot of extra weight behind your hitch and you are pretty much guaranteed to need a 10k hitch for the weight. You also have the added annoyance of finding somewhere to park your trailer every time you pull into a campground.

A dolly is not as much of a hassle as a trailer, but it still adds extra weight and has to be maneuvered out of the way once you settle into your site. Dolly’s are usually small enough to not require storage, but it’s still an annoyance to find a place for one more thing every time you stop.

Dinghy towing requires more initial setup than the other two, but in the long run, it (1) adds the least weight to your RV, (2) is just as fast if not faster than the others to hook up, and (3) you are not stuck finding somewhere to put your dolly or trailer.

So, what do you need to dinghy tow? Let’s take a look…

The Car

You can’t just throw an car in neutral and hook it up behind an RV. Before you hook up a car to be towed 4 down you will want to check your manual and/or online to make sure you won’t fry the transmission. Your options as far as the car are to

1. Own the right car
2. Buy the right car
3. Modify the car if you love your current car

We fell into this third category for our Jeep. Along with my other long list of mistakes, I actually bought a Jeep Wrangler, spent money prepping it to tow, and just before we started to tow it, realized it couldn’t be towed.

Because of the time and money we had into the Jeep prepping it to tow (and we loved the Jeep), we decided to go the modification route.

There are two main ways to make a vehicle that is not towable able to be towed 4-down. Neither are cheap.

The first option is to install a pump that circulates oil to the transmission even when the vehicle is not running. This pump is powered by the motorhome while going down the road.

Although this option is slightly cheaper than the second option, I do not recommend it. These pumps have been known to go out within the first year and when they do, your transmission will likely heat up and be toast before you know it.

At that point, you’ve lost the money you’ve put into the pump as well as your transmission. Not worth the risk in my opinion.

Pump Cost: around $900 + Labor

The second option is to have a custom drive shaft with a disconnect to replace your current drive shaft.

Once this drive shaft is made, you will have a lever under the driver’s seat you can pull that will disconnect the drive shaft and keep the transmission from burning up while the wheels are moving.

There have been a few complaints about having to lube the driveshaft disconnect a time or two each year, but I’ll take that annoyance any day over replacing a pump and a transmission.

Driveshaft Disconnect Cost: Around $1200 + Labor

The Base Plate

The base plate attaches under the front of your vehicle and gives your RV hitch something to attach to.

The plate itself costs around $400 and takes a mechanic 1-2 hours to install it. It is not an incredibly difficult install, but I didn’t want to take any chances, so I hired it out.

The Tow Car Braking System

Unless your towed vehicle is under 3,000 lbs, you are likely going to need a braking system in the United States to keep it legal.

Yes, it costs more money up front, but anything that keeps your family a bit safer should be a top priority when RVing.

I’m not going to get into the dozens of options with braking systems, but if you want to keep things as simple as possible, go with a Brake Buddy or Ready Brake. Either of these systems can be installed yourself in an hour or two.

These two are not “top of the line” braking systems. Especially if you drive a diesel with an air system that could be tied into your towed vehicle brakes. However, they will get the job done and keep you legal.

Braking System Cost: $400 – $1200 + Possibly Labor

The Electrical

The towed vehicle will need lights wired to it that are powered by the motorhome. There are numerous wiring kits you can buy that will run power from an outlet in the front of the towed vehicle to the left and right light brackets in the rear.

As a cheaper alternative, I have seen magnet lights placed on the top of the towed vehicle and then ran to the rear outlet on the motorhome, but if you are using this towed vehicle long-term, you might as well wire it up correctly with a kit.

The RV Hitch

You likely won’t have to put any money into your RV hitch, but you will need to check your manual to see how much weight your hitch can handle.

Keep in mind that just because your hitch can handle 5,000 lbs, you may not be able to pull 5,000 lbs to stay within specs. Your manual should also say how much weight your RV can tow. Sometimes this matches up with your hitch’s capacity, sometimes it is less.

If your towed vehicle weight is less than the hitch capacity, but is more than what your RV is recommended to tow, all is not lost. If you still have weight left on your GVWR, that weight can be distributed to the hitch.

Scenario

Let’s say you have a gas motorhome with a 5k hitch. However, your manual says you can only tow 3,500 lbs. Your towed vehicle weighs 4,000 lbs. Your GVWR is 22,000 lbs, but your motorhome only weighs 21,00 lbs (you can weigh your RV at at CAT scale for about $10). That increases your max tow weight from 3,500 lbs to 4,500 lbs so now you are good to go!

Keep in mind, you can’t go over your hitch capacity. If it is a 5k hitch, it is a 5k hitch. No extra weight on the GVWR is going to help you out.

The Tow Bar

I would recommend getting a tow bar that matches the max weight of your RV hitch in case you change tow vehicles, but at the least get one that can handle your towed vehicle.

Here’s a few recommended hitches and their prices:

NSA RB-9050 Ready Brute Elite Tow Bar: Around $1200 

The Ready Brute is a great option if you don’t have a braking system or a tow bar. This one tow bar includes both in one package.

Blue Ox BX4330 Acclaim 5,000 lb Tow Bar: Around $450

Blue Ox BX7365 Alpha 6,500lb Tow Bar: Around $600

Blue Ox BX7445 Aventa LX 10,000lb Tow Bar: Around $650

All these pieces of the puzzle may seem like a lot to get on the road with a towed vehicle, but it is well worth the initial cost.

Are there any pieces of the “towed vehicle puzzle” I’ve left out? Feel free to ask away in the comments and I’ll do my best to help out or hopefully others can also chime in.