How to Tow a Dolly Behind an RV With Brakes Equipped
- 1). Determine if a hydraulic braking system is fitted to your tow dolly. These are old fashioned, require a physical linkage to the hydraulic braking system of the recreational vehicle (RV) and are prone to leaking. The dolly brakes will deploy immediately when the RV's brakes are used, and the braking force is proportional. If you intend to use a hydraulic braking system, you'll need professional installation of the sender connections on your RV.
- 2). Decide if an electric braking system is fitted to your tow dolly. These are by far the most common device, and although they have many different appearances, they all work by using an electrical signal from the tow vehicle to deploy magnet-operated brakes on the dolly. Some old-fashioned systems use power from a battery on the dolly, but most use power delivered through the tow umbilical from the RV. If you intend to use an electric braking system, you can actuate the dolly brakes in one of two ways: using a "time delay" brake controller or a "proportional" brake controller.
- 3). Determine if you want a Time Delay brake controller to actuate the brakes fitted to your tow dolly. A Time Delay system requires that the driver preset the amount of braking force he wants the brakes to use, and the amount of delay between the RV's brakes being deployed and the dolly's brakes reaching that preset full braking force. These settings are difficult to match, as either the RV will be braking the dolly or the dolly will be braking the RV. This results in uneven brake wear and poor stopping performance.
- 4). Decide if you want a Proportional brake controller to actuate the brakes fitted to your tow dolly. A Proportional system has an inbuilt sensor which reads the deceleration behavior of the RV and transmits a signal which results in the same amount of braking force being applied by the dolly's brakes. The dolly will then stop at the same rate as the RV towing it, anywhere between gentle slowing-down and emergency stopping. This results in even brake wear and good stopping performance.
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