The New Stealth Brake System from Hopkins Manufacturing is an Effective Solution for Dinghy Braking
Motorhome braking with a dinghy in tow can never be too good. While the service brakes in all motorhomes are adequate for stopping the gross vehicle weight rating of the motorhome, longer stopping distances can be expected when towing a vehicle. The problem is exacerbated in gasoline-powered motor-homes that can’t take advantage of an engine or exhaust brake commonly found on diesel motorhomes.
Aside from increased safety, legality is another item that suggests the value of dinghy brake systems; manufacturers cite numerous laws in both the U.S. and Canada that require auxiliary braking for towed vehicles.
Fortunately, motorhome owners have a variety of portable and permanently-installed dinghy braking systems available to them, and recently, another product has been added to the fold: The Stealth by Hopkins Manufacturing Corp., makers of the BrakeBuddy family of dinghy towing products.
The Stealth’s list of features seems to address the main concerns of motorhome owners. The system is out of the way and out of sight, and there’s nothing additional to install, remove, connect or disconnect whenever the vehicle is hitched or unhitched. It’s also a proportional system, meaning that it senses deceleration of the coach/dinghy combination and applies the dinghy brakes accordingly. A dash-mounted controller allows for easy adjustment or manual braking if desired.
The control unit is mounted in the cargo area with the cable and wiring routed 
forward under door thresholds.
In addition to the controller, the Stealth system includes three primary components that help the motorhome and dinghy vehicle stop as one. An actuator unit for the dinghy vehicle is connected via cable and pulley to the brake pedal; a vacuum pump under the vehicle’s hood maintains vacuum to the brake booster; and a specially designed, safety breakaway wiring harness connects the coach and dinghy.
Here’s how it works: When the motor-home driver steps on the brake pedal, the controller senses motorhome braking (inertia) and signals the actuator unit (a small linear winch) to reel in the cable attached to the brake pedal, effectively depressing it. The pedal is “live” (fully vacuum powered), so it doesn’t take a heavy pull to actuate the brakes. Meanwhile, the controller gives the driver a “bb” signal to indicate that dinghy brakes are being applied.
INSTALLATION
To get an idea of how Stealth is installed and how it works while traveling, we observed as the system was installed in a 2011 Honda CR-V, towed behind a 35-foot Ford chassis motorhome. The installation was performed at Camping World,
Cable and wiring are routed under the driver’s door threshold.
Wood Village, Ore. (near Portland) by a very competent and experienced staff. The labor estimate for the Stealth installation was about five hours for a technician who is experienced with the product.
The Honda CR-V offers reasonably good access for the Stealth components, including the 13.5L x 4.5W x 3.5H-inch actuator, the largest component in the system. It would not quite fit under the driver’s seat, so it was mounted behind the left-side passenger seat, occupying a bit of cargo space.
From this location, the cable leading from the control unit is routed forward along door thresholds and under the driver’s seat floor mat to a position below the brake pedal.
Cable housing from the main unit is routed to a pulley bracket, where cable is routed around the pulley and attached to a bracket on brake pedal arm. Excess cable is trimmed.
The cable and a pulley are attached to the floor below the brake pedal, and the cable is connected to a bracket on the pedal arm for a straight, downward pull. Electrical wiring is routed forward from the control unit through the firewall and into the engine compartment.
The vacuum pump is installed in the engine compartment, and a one-way check valve is teed into the CR-V brake booster line so the pump can keep the brake booster at full vacuum while the car is being towed.
The controller, which is the brain of the system, is mounted to the motorhome dash and wiring is routed to a connector at the rear of the coach. This controller is similar to those used in vehicles used to tow trailers equipped with electric brakes – in fact, it can be used for activating the brakes in either a dinghy or a trailer. An inertia sensor detects motorhome braking and electronically actuates the dinghy brakes proportionately.
Space for the vacuum pump is tight in 
the CR-V – sandwiched here between 
the battery and air cleaner.
The Stealth actuator and vacuum pump are operated from the dinghy battery, and the system includes a method of maintaining battery charge by the motorhome alternator. This is handled through the main harness.
The Stealth coiled power cord from the motorhome to the dinghy includes not only the tail/brake light circuits, but also control wiring for the Stealth main unit and vacuum pump. Fortunately for us, Ford includes a wiring harness in the motor-home for trailer brakes and lights; the receptacle for this harness is found under the dash. However, Ford didn’t include a 12-volt DC hot line or a connector spade inside the rear wiring receptacle for such the line, which is required for the Stealth. So, the line and a new receptacle had to be installed
Hopkins’ plug-and-play taillight wiring 
kit includes a diode converter mounted behind a panel in the cargo area.
and an optional Hopkins taillight wiring kit was required for the CR-V.
If, for some unlikely reason, the dinghy were to become accidentally unhitched from the motorhome while on the road, the Stealth coiled wiring cable (tethered by a steel cord to the coach) would be yanked from the receptacle on the dinghy, activating its brakes. After disconnecting the harness plug, a special cover is inserted into the receptacle on the dinghy when you’re not towing to prevent brake activation.
ON THE ROAD
With the installation complete, we dialed the controller’s sensitivity and output settings to maximum, tested the manual control button to see if it would activate dinghy brakes (it did), and unplugged the wiring harness from the front of the car to simulate an emergency breakaway. The Stealth immediately pulled the brake pedal down, and the vacuum pump switched on. We were ready for the next part of our test.
The Stealth kit includes a unique electrical motorhome-to-car wiring harness and receptacle for the front of the vehicle.
To get a close picture of how Stealth would perform, we had a motorhome driver plus a passenger in the dinghy driver’s seat, able to place a finger lightly on the brake pedal to feel its movement. For safety’s sake, this portion of the test was performed in a controlled environment. At speeds varying from 20 to 60 mph, the motorhome driver applied brakes at different levels of force.
Braking effect was modulated well. During light braking, the pedal was pulled down but neither the motorhome driver nor the passenger in the dinghy could feel any surging or jerking; it was seamless. The same was true for heavy braking. With manual activation at highway speed, dinghy braking was barely perceptible, although we knew it was happening – and how much – by monitoring the pedal from inside the dinghy.
During heavy braking (inertia sensing) or with full manual activation, the Stealth did not pull the pedal down enough to take the slack out of the tow bar and hitch (audible), which would have meant that the car was creating drag on the motorhome. But it was close. We could press the pedal lightly with one finger and make this happen, demonstrated by a clanking sound between hitch ball-mount and receiver. Thus, we had what felt like about the right amount of braking.
The brake controller sensed motor-home braking with very little lag, and signaled “bb” each time dinghy brakes were activated either via inertia sensing or manual control.
The goal for a dinghy brake system is that it should enable the car to handle braking for most or all of its own weight – to keep it from adding significant braking load to the motorhome – which in this case the Stealth provided.
The Stealth and taillight wiring kits include all the necessary parts for the job, as well as a set of instructions that feature most of the detail needed for the installation and operation. A few more descriptions would have been helpful, including a brief explanation of Stealth’s operational concept, suggestions on judging performance, adjusting the controller, and a troubleshooting guide. Although installation of the Stealth can be handled by a competent do-it-yourself mechanic, turning the job over to an RV technician with prior experience installing this system may be a wise decision.
The Stealth has an MSRP of $1,099, but is offered at Camping World for $999. An optional Hopkins Manufacturing taillight wiring kit, priced at $79.99, is also required. Many motorhomes already have a “hot” line at the rear of the coach. If not, that installation would be at additional cost.
In addition to the permanently installed Stealth, Brake Buddy offers four portable systems suitable for all types for dinghy braking: Digital Classic, Digital Classic Boost, Vantage Select and Vantage Select Boost. So now, there really is no reason not to use a dinghy braking system, and enjoy the peace of mind that comes with safer travel.
For More Information
Hopkins Manufacturing Corp. | 800-470-2287 | www.brakebuddy.com
