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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
All items arrived in a timely manner. All parts received, in process of installing. So, far all things are good to go.
Very good service, fast response, and willingness to help. The only reason for four stars is that the order was shipped via USPS, which was very slow and provided minimal updates.
Imstallation very easy. Operation easy once you do it a few times.
We just got these added to the site, so I was really excited to go to the first look training so I can learn more. I love that this RVI system is not as bulky as the other portable systems I have had in the past. It is very simple to install, and I really like how it talks back to me, just like my kids Ha Ha! The Bullseye screen is definitely a bonus, it gives peace of mind while flat towing. If things start acting up it alerts you.
I recently got to host a first look for this system and I gotta say, its pretty cool. Its small and lighter than similar systems. It can be a little clunky the first time you install it but once you get through that first install, it becomes a lot easier. Once plugged in, the unit will talk you through how to calibrate and will notify you if there are any issues. If there is, the Bullseye will tell you what the issue is and what needs to be done. Cuts out a lot of guess work. The only thing that needs to be installed in the breakaway. I highly recommend this system to someone who wants something easy to use with next to no install.
Jesse (etrailer.com employee) here. I got my first look at the RVI brake system last week. My first impression was the box and packaging was very neat and clean. The portable system was extremely easy to set up. It talks to you and tells you what to do! This is perfect for DIYers or first timers that don't want to pay big $$$$ to have a shop install a braking system.This system uses the Bullseye monitor which is what really sets it apart. The bullseye is a touch screen and it does all kinds of stuff like real time towing info, diagnostics and braking adjustment just to mention a few.
I have not had the opportunity to try this braking system yet, however, I did phone customer support on two separate occasions while installing this system. They walked me thru the entire installation. I am so thankful for that. I look forward to trying this system shortly. I have no doubt it will work great.
Quick and easy hookup
Poor instruction! It keeps losing being paired, have redone the pairing and will give it another try on our return trip, if the issue continues it will be returned for another brand!
Compressor is bad won't hold pressure. Replacement is already on it's way. Thanks to Chris at etrailer.
The system arrived in excellent working order with easy to read instructions. I have installed the system for a power on test and it worked great. I have not tested it on the road yet, but I have no doubt that it will provide the braking power needed.
Love it, works great. Be prepared to spend more $ because if you want the charge indicator and breakaway to show on the display you need to buy both modules separately. Not mentioned anywhere in the description. Making it a pricey item. But it works great. Otherwise I would have given it a 5 star.
Excellent service and delivery as promised. The box had been previously opened but everything checked out good. I thought maybe it was opened to put rebate information in, but nothing was found. It was a little challenging to find the rebate info on the manufacturers website but finally was able to submit for the rebate.
I had a previous model of same brake for ten years with good service. I replaced it with this one. It worked perfectly but I had to call service to figure out how to set sensitivity and type of vehicle. Nothing wrong. Just unclear directions. I’m happy with brake.
Doesn’t work. Error code 04. RVI says cold weather issue. It’s 90F high and 75F low where I live.
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!
Easy installation, works as advertised.
I have had the RVi3 break since 2018. It developed an air leak in the activator box which was not repairable, so I ordered the new RVi4 to replace it. The brake itself appears the same as the RVi3 but have had some internal upgrades resulting in faster response. The control pad has been greatly improved as it is a round smaller unit that takes less space on the dash, is more stable and very pleasant looking. The round puck that used to be required to be inside has been replaced with a much smaller repeater that goes outside the coach near the chassis batteries and is out of the way. I am reall pleased with the redesign by Curt/Lippert, the new owners.
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
Product had a persistent code 04 immediately upon install. Spoke to curt mfg. the are sending a replacement. Maybe there should be a quality control before shipping.
The Curt RVibrake 4 was delivered today. A day late but the etrailer experts were very helpful and gave a lot of info. Christine was very helpful also. Ill be watching for sales or deals and place another order.
The first one would'nt connect with bullseye and brake(power issue), Soon as the replacement arrives I will try it and return the defective unit. The customer support at etrailer is awesome.
Super simple to use and the wireless bullseye monitor work great. The boot up time on the monitor is about 5 seconds.
From a towing perspective I worried about the system being too intrusive with braking. The RVIbrake performed perfectly. Light and heavier braking when needed and none on gentle stops. Its small and light so its perfect for us to be able to swap between tow vehicles.
Easy to install and use auxiliary breaking option. Installation note - provide a good solid 12+ volts from Battery (+ RV 7-6pin charge line on toad battery)
It seemed to work one time but has never worked right again. It also would not play with the wireless breakaway. Working with CURT/Lippert support for two weeks but nothing worked. Now hoping to return it to somewhere. I only purchased it because my command hub for my RVI3 died. I'm back to using my RVI3 but I don't like not being able to monitor it.
The brake itself works well. The range booster’s effectiveness, however, is very spotty when installed as instructed. We’re in a 45 foot diesel pusher. Installing the booster in the engine bay just doesn’t work well; there’s way too much electrical noise to interfere with the booster causing the Bullseye to constantly lose connection to the RVi brake. The booster really should be designed to install in the coach and powered by something other than those cheesy little alligator clips that you’re supposed to clip directly to your chassis battery.
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.
This replaced an RVi Brake version 1 that we had for 12 yrs. It worked well and I'm sure this will too. This V4 is smaller and lighter. However, the voice prompts are distorted and very hard to understand. I wish they hadn't removed/discontinued the TPMS sensors paired to the monitor. The monitor should also be rechargeable rather than requiring another wired connection on my already cluttered RV dash.
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.
Condition: Like New
Notes: May have damaged packaging or minor cosmetic blemishes.
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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?