Our 4 Down Towing Set Up: Part 2 – Braking System

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In Part 2 of our 2 part blog/video series about 4-down flat towing, we discuss the different types of braking systems, as well as what specific braking solution we chose and why. 

We share some specific information about our toad which may help you be aware of any special needs of other towed vehicles you may be considering. Some additional information that will be especially helpful if you choose to tow a Jeep Cherokee Trailhawk as we do. We also let you in on the little secret of how we managed to keep our Jeep rescue tow hooks and how you can keep yours too for when you aren’t towing.

If you haven’t already seen part 1 of this 2 part series about our tow bar, you might want to start by checking that out first – click here.

Let's jump into towing braking systems

As you probably know, we like to do extensive research before making large purchases. A set up for towing a vehicle four down behind a motorhome definitely qualifies as a large purchase in our book! Four down towing systems like the one we have costs around $4,000 all up installed. That includes the tow bar, braking system, wiring for lights, brackets, locks, and all of the related professional labor for the installation.

Prices will vary depending on your specific tow vehicle and the products you choose for your set up. If you have the tools, talent and time, you may be able to save some money by doing the installations yourself. This is a big investment so you’ll likely want to ensure you’ll be keeping your towed vehicle for a while. Which is what we were mindful of when choosing our 2015 Jeep Cherokee Trailhawk.

Let’s talk about towing braking systems and the things you’ll need to consider.

Why You Need a Braking System for Your TOAD

You might hear some people say ‘my motorhome doesn’t even know my toad is back there’. The truth is… it does. If you ever need to stop quickly, having a little extra help can make all the difference between a close call and an accident. You can adjust the sensitivity and strength of most braking systems for towed vehicles.

This allows you set up the system so that both vehicles do the appropriate percentage of the work. For example, if you are towing a 5,000 pound vehicle behind a big 50,000 pound tag axle motorhome, the toad is only around 10% of the total weight. But if you were to tow that same 5,000 pound vehicle behind a 10,000 pound Class B your toad is over 30% of the total weight and will need to do more braking to safely stop the combination.

At the very minimum, your towed vehicle should have a system that will apply the brakes in the event that it becomes separated from your towing vehicle. This is often called a breakaway system. Virtually every state requires towed vehicles to have a braking system installed. The rules around the minimum weight of the vehicle required to have braking can vary from state to state. If you are planning on traveling all around the country, you should plan to be covered in the strictest state you travel through. Not just the state you are from.

Types of Braking Systems

Let’s start with an overview of the towed vehicle braking system basics to help you understand why we chose what we did. And consider which might be best for you.

The two main approaches to towed vehicle braking systems are proportional and progressive. 

Progressive braking systems

Progressive systems activate the brakes on the towed vehicle any time you touch the brake pedal of the towing vehicle. They progressively ramp up braking force while you have your foot on the brake pedal, regardless of the pressure you apply. 

Some systems are more advanced than others, with limits on how long the brake pressure is applied. The main point is that the pressure is not proportional unless you actively think about it.  To be proportional, you would need to apply the brakes on the towing vehicle the same way you know the towed vehicle brakes will be working, ramping up the pressure over time.

Proportional braking systems

Proportional systems provide equal pressure to the braking systems of the two vehicles. Press lightly on the towing vehicle pedal, and the brakes are pressed lightly on the towed vehicle. Similarly, when pressing hard on the brake pedal, both sets of brakes press hard. Some proportional systems are directly proportional by integrating the two systems with air pressure. Others are virtual proportional using accelerometers to help adjust braking pressure.

Proportional systems are often viewed as superior because of their more direct relationship. But, it depends on the application, the driver, and the vehicles, which might be best for you.

Installing a Braking System for a Towed Vehicle

Some systems require lengthy installations into both the towed and towing vehicles (the motorhome) but require less work in daily use. Portable systems (like a BrakeBuddy) have simple initial installations. But they require inserting and removal of the portable system every time you hook up to tow.

You’ll want to ask yourself a couple questions to help you make your decision. How often do you hook up to tow? How many different vehicles do you tow? Both will be deciding factors on which system ends up being a better fit for you. We had just bought our Jeep which we plan to keep for many years, and it is the only vehicle we tow. So we were comfortable making a permanent braking installation into the Jeep.

Which Braking System Did We Choose and Why?

We chose the Roadmaster Invisibrake system. There were a number of reasons for this choice. First, as mentioned in the tow bar post, we really like Roadmaster as a company. We appreciate their educational approach and have a lot of faith in the exacting quality of their products. 

Second, we loved the simplicity of the Invisibrake system. Once the Invisibrake braking system is installed, there are NO additional steps required when hooking up your vehicle to tow, or when disconnecting. The system works off of the brake light signal from the wiring installed for the lights. There is nothing to be placed between the brake pedal and seat (as with many other systems). And no additional connections at the front of the vehicle.

Invisibrake installation requirements

While the Invisibrake system does require a more involved installation into the towed vehicle, it is a one-time installation. The largest physical piece of the system was installed neatly underneath the driver seat of our Jeep. If your vehicle doesn’t have enough room under the seat, the system could be installed in many other locations.

There was no installation required on our motorhome. All we need for the RV is a wireless Brake Monitor that we plug into a 12v receptacle in the front dash of our motorhome. It has a green light to indicate the system is ready. A yellow light that indicates the brakes are being applied and a red light to provide a warning in the event that something goes wrong.

The amount of installation required in both vehicles was a big consideration for us. We had just bought our 2015 Jeep Cherokee Trailhawk and plan on keeping it for a long time. Having owned our Tiffin gas motorhome for over three years now, we expect to change our RV before changing our tow vehicle. So we wanted to avoid the need for a lengthy installation into the motorhome itself.

Charging the Vehicle Battery While Towing

The third reason we chose the Invisibrake, is that it actually charges the battery of our Jeep while it’s being towed. Most portable systems and some other systems installed in towed vehicles use small air compressors to build pressure. This pressure is used to press the brake pedal. These compressors usually get energy from the towed vehicle battery via the 12v plug. Over time, this, combined with running the lights or other systems, can drain the battery of your toad.

Our Jeep is especially sensitive to this issue as it has electronic steering that also needs to remain active when being towed. This system can drain the battery in as little as three hours while towing. So, we needed another source for charging the Jeep battery, as we often tow for longer than three hours on a travel day.

Of course, we could have chosen to buy a separate battery charging system. But that is just another system to purchase, install and remember to connect when it is time to tow. We wanted to keep our setup as simple as possible. It’s important to note that the Invisibrake will only charge batteries if your lights are ON in the towing vehicle (motorhome), to send the electrical current through.

Update August 2019: The battery drain with our Jeep’s electronic steering is so high, that it is recommended that you add additional battery charging capacity beyond what can be supplied through the Invisibrake.  Roadmasterinc added an extra charging line for us. To learn more about what prompted the upgrade check out this related article when something went really wrong.

Why Does Invisibrake Keep the Brakes Active?

Part of the reason the Invisibrake is set up to charge the batteries is that the system itself requires an ‘active’ braking system. As mentioned above, most braking systems installed in towed vehicles work by pushing the brake pedal. This requires a lot of force because most modern vehicle braking systems require the system to be active to maintain the light pressure feel of the brake pedal.

Have you ever turned off your vehicle and tried using the brakes multiple times with the systems off? The ‘dead’ pedal will require much more force to achieve the same result. Invisibrake keeps the braking system active and uses a cable BEHIND the brake pedal and ‘pulls’ rather than pushes on the pedal. This is possible because having an active braking system requires far less pressure to achieve strong braking power.

Pulling from behind the pedal also avoids the need for having any bulky item between the driver seat and brake pedal. This can be an advantage if you need to quickly jump into your tow vehicle to drive it. With the Invisibrake system, there is no braking system to remove first before you can drive the towed vehicle.

Working with a Progressive Braking System

Some may perceive a potential disadvantage to this system in that it is a progressive braking system, rather than proportional. However, I tend to use engine/exhaust braking for the majority of my braking force when driving the motorhome. Doing so saves the regular brakes for when I really need them.

I also tend to use my normal brakes by applying shorter, firmer pressure, just like progressive systems do. So with just a little extra thought, I am able to have my progressive brakes behave very similar to a proportional system. The Invisibrake will steadily ramp up pressure for 8 seconds. So I make sure to not apply the brakes lightly for more than a few seconds to avoid having the Jeep brakes do more than their share of the work.

Invisibrake is a very intelligent system. It doesn’t just ramp up and hold that high braking pressure. When you let off the brake in the motorhome (or other towing vehicle), it will back off pressure on the towed vehicle. Also, if you happen to rest your foot on the brake lightly for too long, the system will only hold the brakes for a maximum of 15 seconds to reduce the risk of overheating them.

This is also a great feature for when you are sitting at a stop light. The brakes will be fully released from the tow vehicle when the traffic light turns green. Some of you more advanced folks might be wondering about what happens when you turn on hazard lights, knowing that hazard lights often activate the brake light signal. Don’t worry, the Invisibrake recognizes the pattern and will not activate the brakes when the hazard lights are turned on.

Wiring the Jeep Tail Lights

The next element of our installation was wiring the Jeep for the tail lights. We wanted to have the tail light signals of the Jeep match the lights of the RV. Magnetic lights that stick to the outside of the towed vehicle are fine for temporary use. But we wanted a more permanent installation.

In our opinion, if you are going to go to the effort, time and expense of setting up a vehicle to tow four down, it’s worth taking the extra step and having the tail light wiring integrated. It looks much better, is more simple in daily use, and more consistently reliable.

Components of our 4-Down Towing Setup

Here are the components that make up OUR specific 4-down towing and braking system for our motorhome and 2015 Jeep Cherokee Trailhawk. It is important to note that this system setup (and therefore costs) may vary depending on your tow vehicle and specific brackets, wiring etc related to that. But this will at least give you a good idea of what to expect:

Roadmaster Nighthawk Towbar

Invisibrake Braking System

Towbar Bracket Kit (these are individual to the toad vehicle)

Wiring Kit 

Receiver Lock

Brake Light Switch

 We also got the Roadmaster Towbar Cover Storage Bag to protect the tow bar and wiring, and keep it all together and tidy, plus a Towbar Accessory Storage Bag.

Jeep Specific Towing Information

Another reason we really liked the simplicity of the Invisibrake braking system (once installed, it’s set and forget) is because our Jeep Cherokee Trailhawk requires a very lengthy process to put it into neutral and prepare it for towing. For some vehicles, especially those with manual transmissions, it can be as easy as simply pulling the gear shift out of gear and into neutral. That, and of course, making sure the parking brake has been released. Simple vehicles like that can be ready in about five seconds.

Believe it or not, our Jeep (unlike some others) has an 18 step process listed in the owners manual just to get the vehicle into neutral. This can take a few minutes initially. But that’s not the end of it. The steps for getting our Jeep ready to tow actually takes much longer than connecting the tow equipment (that takes less than two minutes). If you’re interested in seeing the steps, click here to download the 3 page document that we follow when getting set up to tow. Putting the Jeep into Neutral and restoring it for regular driving again. It looks a bit overwhelming at first. But once you’ve done it a few times, it actually isn’t too bad. 

The Jeep ‘death wobble’ and how to fix it

It was discovered a few years ago that some Jeep Cherokees (2014-2016 models) may develop a steering wobble when being towed. This is commonly referred to as “the death wobble”. Don’t panic – it’s fixable! We were aware of this before we even bought our Jeep. We discovered this issue during our research process on the suitability of the Trailhawk for towing. You can learn more about this in forums like FMCA and IRV2. Because there is a fix for it, it didn’t deter us from buying the Trailhawk, We really loved it and still do.

Update August 2019: We actually experienced the ‘death wobble’ with our Jeep. Read more about it and watch the related video here. 

Here’s how to prevent the ‘death wobble’ from happening.

You need to have an aftermarket accessory installed. It’s called a Mopar Flat Tow Wiring Kit (Part Number 68321424AB). And it will keep the electronic steering active in tow mode. This aftermarket wiring kit helps prevents the ‘death wobble’ from occurring, which prevents damage to the steering and other components and other potential incidents.

We took our Jeep to a dealer that already had the part in stock for the installation. Some dealers we called had never even heard of it while others were familiar. This can be a complex and time-consuming installation requiring soldering wires into the existing wiring kit. So this isn’t an ideal DIY project. We wanted the job to be done by a dealer experienced with the process to ensure a successful install. Having an experienced shop would also reduce the number of labor hours for the job.

The cost, including parts and labor, came to about $450. This also included mounting a toggle switch in the console between the seats and a 10 AMP fuse that goes under the hood. We recommend you call around to a few Jeep dealers to find one that is familiar with both the part and the wiring kit install to ensure it is done properly and time efficiently. This is the system that we referred to above that drains the battery if being towed more than three hours. That is also what increased our interest in having a braking system (Invisibrake) that charges the battery while the Jeep is being towed.

How long does it take?

As a result of this mod, we also have to add a few extra steps to the process of getting the Jeep prepared for towing. All up, we estimate it takes 2-3 minutes to get the Jeep into neutral and ready to be towed. That’s on top of the 2 minutes it takes to connect the towbar. Now that we’ve had a bit of practice, it takes us about 5 minutes all up, to get fully set up and ready to tow.

We felt it was important to mention this aftermarket mod here – even if you aren’t planning to tow a Jeep like ours – as some other vehicles might be listed as appropriate for towing four down. But those vehicles may require aftermarket modifications for optimal safety and longevity. You will likely need to research deeper than just an owner’s manual, and the Motorhome Magazine Dingy Towing Guide, as we did. And definitely DO NOT rely on what a car dealer tells you! Even if they say the car is towable. Rmember, they are trying to sell you a car, not help you be a safe RVer!

How to keep your Jeep's red rescue hooks

Ever since we announced we were flat towing the Jeep, we’ve had a ton of questions asking how we managed to keep our red ‘rescue hooks’ after installing our four-down towing setup. The Jeep Cherokee Trailhawks come from the factory with red rescue hooks on the front and rear of the Jeep. These aren’t just for looks. They also have a function if you get stuck out on the trail, so you can get towed out. We liked both the look and function of the hooks and wanted to find a way to keep them.

Most Jeeps we see that have been set up to tow 4-down no longer have the rescue hooks as the brackets for the tow bar usually need to be installed where the hooks used to be.  That’s because that area is a strong structural point for connecting the tow bar equipment. We found a way to have the best of both worlds by working with a welding/fabrication shop to make us a custom solution.

We got an extra set of tow bar brackets, had the ends cut off, then replaced the normal brackets with the red hooks by welding the hooks to the extra brackets. This allows us to install the brackets with the hooks back onto the Jeep anytime we like. The hooks are also extremely functional because they are mounted in the tow bar brackets which are rated for high strength. It’s definitely not something everyone will want to do. But we think it is a really cool extra step and seems to have attracted a lot of interest. So if you’re willing to buy an extra set of brackets and find a welder to do the job, it’s a great way to retain the look of your stock Jeep.


Well, that wraps up just about everything you need to know about our toad vehicle braking system. And concludes our two-part series on our chosen options for towing our vehicle four down. Now that we’ve been flat towing with the Roadmaster Nighthawk tow bar and Invisibrake for about six months, we are happy to report that we love our entire setup. 


2022 Update: We are still super happy with this towing set up 5 years later.


We’ve been extremely happy with our choice and are confident our towing setup will last us for many years to come. If you want to learn more about the products we chose, you can visit the Roadmaster website. We hope you found this series helpful and it provided some valuable education on vehicle towing and braking systems. Hopefully it has given you some great options to consider for your own needs.


Got questions or comments? We’d love to hear from you!

Did we miss anything? Are you looking for a towing solution? Already have one and want to share your experience? Please leave us a note in the comments below. We’d be happy to answer and always love to hear from you.

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