RV Tech Savvy: Know Your Emergency Breakaway Switch

Q. I have a trailer with hydraulic surge brakes, which has a safety chain attached to an emergency-brake actuation lever. How do I attach this breakaway chain in addition to the other two safety chains?

I know the safety chains are supposed to make a cradle under the tongue and keep the tongue off the road, in case it comes loose from the hitch ball. But in such an emergency, should the actuating chain to the emergency-brake lever activate those brakes while the trailer is still safely chained to the tow vehicle?

— L.G., Marengo, Indiana

A. As its name implies, L.G., the breakaway safety device is just that — it activates the trailer brakes in case the trailer separates completely from the tow vehicle. The safety chains are designed to keep the trailer in control and with the tow vehicle, until the driver can bring them both to a safe stop in case the trailer coupler separates from the hitch ball; so, the two devices really don’t
work together, per se.

So no, the emergency-brake actuation device should not work if the trailer is still held to the tow rig with the safety chains. In fact, the extra stress of a 100-percent emergency trailer-brake actuation could break the safety chains, making matters worse.

The safety breakaway-device chain should be attached to a solid portion of the tow rig’s hitch using something strong and secure, such as a threaded quick-link chain fastener.

— J.J.

Jeff Johnston, TL technical director, started RVing at age 6. During his more than 20 years as a writer/photographer, he has worked for Truckin’ and Four Wheeler magazines before joining TL’s technical staff in 1985. Johnston also has produced an award-winning travel video and TV commercials.


  1. How do you attach safety chains to a gooseneck adapter??
    I recently purchased another truck to tow my fifth wheel and it was monitarily and convient to utilize the gooseneck ball and just purchase an adapter.
    Well I’ve purchased the 30,000# adapter 15,000# chains (ea) and installed the !5,000# flip rings on the hitch plate, only to find there is nothing available to connect the chains to the adapter with the weight rating is above 5,000#. Is there a solution, other than going back to a fifthwheel hook up?


Please enter your comment!
Please enter your name here