Towed Vehicle Braking Systems

More consumers are taking an interest in this subject. The British Columbia statute required auxilliary braking systems for towing in BC -- and for a period they enforced it. Also Ford & Chevy chassis began saying in their limitations that max towing design was under 2,000 pounds. Today there are is no significant enforcement on braking systems, even though most states require and enforce auxilliary braking systems on normal travel trailers over a relatively low threshold weight limit. Since the laws on toads are already there, there is potential liabiiity in the future.

It's therefore essentially a safety consideration. The urgency for an auxilliary braking system depends in part on comparing the size of motorhome versus size of toad.

Three basic approaches to braking systems.

1. Mechancal surge break in Autostop (Blue Ox). When MH brakes applied, toad pushes against receiver. That movement is translated into mechanical application of toad brakes. Anytime the toad's brakes are working, a light on the dash confirms they're working. Drawbacks: Needs to be level; and can't back up. To do so would be to apply the brakes on the toad. Something would give... By federal law, every car needs to be able to stop w/out power assist, thus the fact there is no "power" brake in operation is overcome. Two hour installation. It's adjustable so that easily changed to ease off on braking when e.g. downhill using an exhaust brake you don't wear out toad brakes.
2. Hydraulic brakes. Problem here is most people don't want to assume the liability. Complex, cost, installation time, risks.
3. Air systems. Generally use air system to push the brake down.

Many are non-proportional systems, meaning in panic stop, you'll get standard braking.

How easy are these things to hook up? Be sure to check that when looking at braking systems.

Breakaway systems. Most people aren't using breakaway systems. Braking systems are outselling breakaway systems by over 100 to 1.

To be safe and legal every motorhomer towing a toad should install a toad brake (TB). The cost of a TB is less than $1000. This cost is absolutely justified and necessary to reduce risk of person and property loss. Stopping most motor homes is difficult enough without adding the weight of a toad. This article will help you understand and select the best TB for your application.

Important Attributes of a TB: There are many TB designs to choose from so understanding how each unit functions will help you pick the best one for you. The important attributes are to be non-intrusive, have adequate power, activated positively and have an operations monitor to tell you in the motorhome that the brake is working properly. It should be adjustable, easy to maintain, have an effective "Break-Away" function and be easy to connect, disconnect and store. The Break-Away function stops the toad if it should ever become disconnected from the motorhome.

Non-Intrusive: A TB should make the least changes or alterations to the motorhome and the toad. Even though we are protected by the Magnisson-Moss Act, warranty repair of a modified braking system is difficult to arrange, when the service manager points to the modified hydraulic line, vacuum line, master cylinder, or any other component, and says "That’s what cause the problem!" The more modifications required the more failure possibilities there are. The fewer modifications the better it is.

Braking Power: TB’s that push or pull down on the unassisted brake pedal of the toad require 200 lbs. to 400 lbs of pressure to cause the toad to safely stop from highway speed. That pressure can break the brake pedal housing. Un-assisted brakes were used on passenger vehicles prior to the 1950’s. Have you ever had to stop a modern car when the engine was not operating? It is very difficult and takes a lot of strength. Regulations require that a person should be able to stop a vehicle with then engine not running. Braking takes 20 lbs. or less pressure when there is assistance (vacuum) available. TB’s that use the charged vacuum assist design of the car are better than those that don’t. At least two designs use an "air over hydraulic" scheme that inserts an additional air chamber into the hydraulic system. I have found this air of hydraulic system to be very satisfactory. To make the Break Away work there must be enough power to stop a toad if it should ever break loose from the coach from highway speed in a reasonable distance.

Positive Activation: TB’s should only be activated when aggressive or emergency braking is required. The motor home’s normal braking and compression braking are more than adequate for normal traffic. Exhaust Brakes on Diesel engines motor homes are effective methods of slowing the combination while descending a grade assuming you were in the right gear that the top of the hill. The best design senses when the motorhome service brakes are applied and then applies braking on the toad immediately. Designs that use a time delay to overcome control inadequacies delay needed braking action and thus are less effective. TB’s that use surge sensing to cause hydraulic pressure or mechanical pulling or pushing on the brake pedal do not necessarily activate when the motorhome brakes are engaged. If surge TB’s are not installed and adjusted properly they will prematurely wear out the toad brakes because it applies brake power when it is not needed. This happens when descending a mountain grades, backing up, driving over speed bumps, etc when no brakes should be applied. Momentum change sensing activation, like with a pendulum or gyroscope, can also cause improper application of the toad brakes. I favor activation when the motorhome driver presses on the brake pedal of the motorhome.

Adjustment and Verification of Operation: Ideally a TB would require no adjustment after initial installation. If it does required periodic adjustment, that process should be extremely easy. The operation of the TB should be annunciated in the motorhome with a status light so that the driver can continually verify its operation and not just hope it is working. A TB that allows verification of operation while driving the toad solo has a real advantage.

Ease of Connection/Disconnection: An ideal TB should be easy to connect and disconnect from the toad through simple quick disconnects on wires or hoses. It should be easily stowed for solo operation. There should be no need to adjust the brake every time it is used. If this is not true then some of us will get laze some times and say "I am only towing a few miles, so I won’t hook it up this time". As we have heard many times the most dangerous mile we travel is the very next mile.

Ease of Maintemance: Required maintenance should be simple and easy for anyone to perform. The less maintenance the better the design is.

I have personally tested six different designs. I have studied most of the others. I recommend the VacBrake by ToadStop for gas motor homes because the motorhome engine produces the required vacuum pressure. I like the M&G system for diesels with air brakes because it uses an air-over- hydraulic design. Both are immediately activated when the motorhome service brakes are depressed. Again my opinion is that you need a toad brake during emergency braking maneuvers. Good driving habits like having an adequate following distance, being in the right gear at the top of the descent, defensively signaling your intentions, etc will allow you to only need to use the service brakes sparingly. Driving this way is very easy on the passengers and equipment. To be safe and legal a Toad Brake is necessary.

Supplemental Braking System for Towed (Toad) Vehicles

I have written many articles on Supplemental Braking Systems that are posted on this web site and try very hard to be objective when evaluating any system. The analysis of the operation, design and quality of a supplemental brake from paper records is fairly easy to do. Deciding whether to recommend one system or another is another thing. I have personally tried six different systems by installing the brake on my toad and using it for a few thousand miles. I also do a few comparative tests that are not scientific because it is impossible to duplicate the exact same conditions over a few years of evaluations. I don’t have the funding to get samples of all the systems, mount them on the same toad, and test them behind the same coach. Comparing the effectiveness of various systems that has been reported in my articles is based on common sense and a few thousand miles experience towing with the brake installed on my toad.

I recently installed the M&G Engineering System on my CRV and have driven this combination for about 4000 miles. I found this supplemental brake to be very effective and easy to use. My coach is a diesel pusher, so the compressed air necessary for the air over hydraulic system to work was readily available. I previously described this system, but will repeat here how it works. A model specific cylinder is inserted between the vacuum assist unit and the master cylinder. A rod is inserted into this cylinder that extends brake pedal rod so that there is not change to the operation of the toad brakes when driving solo. To get enough room to install this cylinder took a little pulling to get the existing brake lines to move enough to accommodate the cylinder. This insertion is the only modification made to the toad. When towed, this air over hydraulic cylinder that is unique for every model vehicle is powered from an air line that comes from the rear axle of the coach. This new air line is "t’ed" into the brake lines providing air pressure to the rear brake hubs. Two standard air line quick disconnects are used to join this line to the cylinder in the toad. The only connection between the toad and the coach is this one air line. Connecting and disconnecting is a breeze and takes less than one minute. You can see immediately that the toad’s brakes are applied at the same rate as the coach’s brakes. I was reluctant to test this system because it makes two modification to existing brakes, one by adding the cylinder to the toad and the second tapping into the brake lines of the coach. The Break Away Option requires an air accumulator tank being installed on the toad. This tank has a check valve so that pressure is stored after the service brakes on the coach have been applied a couple of times. A standard Break Away switch operates activate an air valve that uses this stored pressure to apply and hold the brakes on the toad. After reviewing the installation and experiencing the effectiveness of this design, I find it very acceptable for installation on Air Brake Coaches. M&G Engineering can be reached at 1-800-817-7698.

The M&G System for hydraulic braked coaches is more complex because an auxiliary air compressor and proportioning valve connected to the coach’s brakes are required. The system is more complex because there are two more components to adjust and possibly fail. Because of the additional components, the M&G System is more expensive when applied to a coach that does not have air brakes.

Why do I Need Supplemental Brake for my Toad?

The most significant difference between driving a automobile and a motorhome that weighs more than 10 tons is getting it stopped. There are many miles of driving a motorhome when you don't even touch the brake pedal, even descending steep mountain grades while using an exhaust brake and starting at the proper speed at the top. But when you need to do an emergency stop, it takes 200 to 300% more distance to get a coach stopped compared to a car. That's one of the reasons that safe drivers double the following distance behind traffic, even though cars typically fill up that space and you then have to slow a little more. Adding 10 to 20% more weight to stop, that is a 2500 to 4000 lb. Toad, only makes safe stopping significantly more difficult.

States and Provinces of Canada limit the un-braked towed weight to from 0 lb. (North Dakota) to 10,000 lbs. (Massachusetts) with most limiting to 3,000 lb. Most of these authorities also require a "Break-Away Brake" as well. I do not know of any state that is currently citing motorhomers for violating these limits, but that does not mean that they won't start in the future. Most of you remember that British Columbia started to issue citations for any towed car over 3,000 but was forced by pressure from the tourist board to raise the limit to 4400 lb. I hope we can be responsible enough so that we don't have to have "Big Brother" further limiting our freedoms.

Which one of you really wants to risk serious personal or property damage for the want of a device that costs around $1000 installed? I strongly recommend that everyone towing a vehicle behind a motorhome without a supplemental brake, reconsider the safety of that choice. I have read recently that Insurance Companies are considering giving a discount for toads with brakes. I hope they do so that we will be further influenced to get with the safety program, and get a brake for each and every toad out there.