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Imagine prepping for your trip and having your braking system ready in less than a minute. With the RVibrake 4, the audio assistant guides you step by step, so there's no fumbling or guesswork, just a quick and reliable setup every time.
A braking system is a must when towing a vehicle behind your motorhome. Without it, the extra weight of your toad (towed vehicle) puts more stress on your RV's brakes, makes it harder to stop safely, and can even put your warranties at risk. Most states legally require one, and if you're ever in an accident, not having a braking system could leave you with major insurance and liability problems. Plus, without one you don't have a breakaway safeguard. If your toad ever disconnects, there's nothing to bring it to a stop.
If you choose the wired route, the most involved step may be drilling through the firewall if there isn't already an open pass-through. Once that's handled, the rest is simple. Clip on the brake pedal claw, plug the unit into your car's 12V outlet, press the "Auto Position" button, and follow the voice prompts. That's it. If you'd rather avoid drilling or running wires entirely, the wireless adapter keeps the install uncomplicated while still giving you full breakaway protection.
Second, it gives you a lot of flexibility. Moving it from one toad to another is simple. As long as you have a second vehicle breakaway kit (RVi97FR - sold separately) installed, the RVibrake 4 can be set up in another car in minutes. That means you can switch up which vehicle comes with you on your next camping trip. And if you trade in your toad down the road, getting the new one ready for this unit is a breeze.
The RVibrake 4 has a built-in inertia sensor that knows when your motorhome slows down. As soon as it senses that change, it presses your toad's brake pedal at the same time and with the same force you apply up front. From a gradual slow down at a red light to a hard stop in an emergency, the toad and the RV will brake together. That's what makes it a proportional system.
The in-cab wireless controller, called the Bullseye, lets you adjust the sensitivity of the inertia sensor to determine how hard the RVibrake 4 system will push on the brake pedal. It's totally up to you how sensitive you want it to be; a heavier vehicle will probably need more sensitivity, while a lighter one doesn't need to brake so hard.
If you're towing a hybrid or any car with continuous-power-assist brakes, all you have to do to use the RVibrake 4 is choose Active in the "Brake Type" setting on the Bullseye monitor.
The RVibrake 4 also comes with a breakaway switch, an absolute must for safe flat towing. If there's ever an emergency situation where your toad becomes detached from the motorhome, the breakaway switch will immediately activate the brakes and bring your vehicle to a stop.
This switch mounts to the front of your toad and plugs directly into the unit. It includes a pin that connects to your RV's hitch receiver with a breakaway cable. If the toad and RV become disconnected, the cable will pull the pin out of the switch and trigger the braking system.
Supplemental braking systems draw power from your toad, and over long travel days that can slowly drain the battery. The Curt RVi Series Towed Battery Charger+ (RVI74FR - sold separately) solves that by letting your toad pull power directly from your RV while you drive.
It doesn't just charge. It also sends battery status information to your Bullseye Monitor, so you can see exactly what's happening in real time from the driver's seat. No guessing about your battery status or surprises when you unhook. If you're towing for full days at a time, this is one of those upgrades that adds real peace of mind.
Flat towing can be a much more convenient way to take your car RVing with you than using a trailer or a tow dolly. It'll save you storage space both at home and at the campsite, and it takes less time and hassle to hook up. To flat tow your vehicle, there are 5 basic components you're going to need: a tow bar, a base plate kit, a safety cable set, tow bar wiring, and a flat tow braking system.
| For the RV | Between the RV and Towed Car | For the Towed Car |
|---|---|---|
| Hitch | Tow bar | Base plate |
| Wiring plug | Safety cables | Braking system |
| Wiring adapter cord | Wiring kit/diodes |
The custom-fit base plate installs on the frame of your toad so you can connect the car to your RV with a tow bar. Hook up safety cables between the vehicles to ensure that the toad does not separate from the motorhome if the tow bar becomes detached. Tow bar wiring syncs your vehicle's signal lights with your motorhome's tail lights, as required by law in most states. Finally, the flat tow braking system - also required in most states - activates the brakes in the toad when you hit the brakes in the RV, making for smoother, safer braking, and preventing wear on your motorhome. If you'd like help installing the components for your flat-tow set up, check out our Installer Locator to find an installer near you.
Customer Satisfaction Score:
89% were satisfied with this product
11% of customers were not satisfied
Ratings & Reviews
Kate F.
9/14/2026
Happy to hear you are happy with the product Johnny! Bummer about the directions though, I hope they made note of that when you called so they can make some changes to them. Where did you go for your first big adventure with the new braking unit?
Mike L.
8/19/2026
Curt tells me that the 04 error code also indicates a high temperature condition. I see we're in the process of reshipping a replacement, so please let me know if you need further assistance!
Kate F.
11/26/2025
Glad to hear that they made the right changes Randall! What kind of RV do you have, any fun trips this year?
Kate F.
12/1/2025
Kate F.
5/6/2026
Thanks for sharing your experience, especially with a setup like a 45 foot diesel pusher Mike. It’s good to hear the braking itself is working well, so let’s see if we can get the connection side of things cleaned up. On longer coaches, having the range booster in the engine bay can cause interference and lead to the dropouts you’re describing. We’ve seen better results when it’s moved inside the coach or to a more central spot. It can also help to keep the antenna vertical and not blocked by metal. We appreciate the note on the alligator clips too. They’re meant to keep the system portable, but we understand wanting a cleaner, more permanent power option on setups like yours, and we’ll pass that feedback along.
Do you have a question about this Flat Tow Brake System?
Condition: Like New
Notes: May have damaged packaging or minor cosmetic blemishes.
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Bobk
8/8/2026
Failed on first use, and had to be replaced, due to loss of setup while driving, and a malfunctioning Auto Setup button.