Pasted in below is a write-up on towed-vehicle braking systems I did awhile back for someone who asked. I don’t expect everyone to agree with everything it says – I’m providing it here for what it may be worth.
Dead Pedal Braking versus Power Braking
Some of the systems on the market energize the towed vehicle’s power brakes while others do not. Those that don’t obviously have to push harder on the towed vehicle’s brake pedal to provide any meaningful stopping assistance.
I’ve never owned a dead pedal braking system and don’t intend to. I’m not implying they don’t work, just that I prefer braking systems that energize the towed vehicle’s power brakes.
Inertia Activation versus In-Synch Activation
Many towed vehicle braking systems, probably the majority of them, rely on an inertia (deceleration) sensor or surge detection to trigger activation of the towed vehicle’s brakes. Other systems tap into the air brake system of diesel motorhomes and are able to apply the towed vehicle’s brakes exactly in synch with the application of the motorhome’s brakes.
I’ve owned and used both types. While the delay associated with the inertia activated systems is very slight, it is nonetheless true that those systems cannot and do not apply the towed vehicle’s brakes quite as quickly as the in-synch systems. As such, I have a personal preference for in-synch systems. That said, there are several very good inertia-based towed vehicle braking systems on the market.
Portable versus Permanent
Some towed vehicle braking systems are portable and can easily be moved from one vehicle to another. These systems typically require little or no upfront installation work, but have the disadvantage of having to be put in place each time you’re ready to tow and removed each time you want to drive the towed vehicle. Other systems are more permanently installed. These systems require more time and effort upfront, but once installed the time to hook up for towing and to unhook for driving is very minimal.
I’ve owned both types and have come to prefer the more permanent systems, simply because of the reduced time and effort they require once installed.
Conclusions
In my opinion, the best towed vehicle braking systems energize the towed vehicle’s power brakes, operate in-synch with the application of the motorhome’s brakes, and are permanently installed, thereby minimizing the time and effort required to hook up and unhook. One such system is the very popular Air Force One from SMI (now part of Demco). M&G Engineering also offers systems that meet those criteria. The BrakeMaster system from RoadMaster is similar, but does require an activation cylinder to be installed for towing and removed for driving.
SMI’s Stay-In-Play Duo is a very good inertia activation system that energizes the towed vehicle’s power brakes and is permanently installed, thereby by minimizing hook up and unhook time.
Among the portable, dead-pedal, inertia activation systems, the RVI Brake is one of the best and easiest to use in my opinion.
For more info:
SMI Air Force One –
http://www.demco-products.com/rv-towing ... -force-one
M&G Engineering –
M & G Engineering - Car Braking Systems: Home Page
RoadMaster BrakeMaster –
http://www.roadmasterinc.com/products/b ... ake_m.html
SMI Stay-In-Play Duo –
http://www.demco-products.com/rv-towing ... n-play-duo
RVI Brake –
http://www.rvibrake.com