Break away brake cable

[STJ]

While helping a friend set up his weight distribution hitch for a new trailer, I noticed his electric break safety cable hanging very low to the ground. I have mine zip tied to the safety chain to prevent this, which I advised him to do the same.
This got me thinking, if the trailer ever did come off the ball when should the safety cable activate the trailer breaks?
Before the trailer reaches the end of the safety chains, or after the chains come off. I would think it should the first option holding the chains never come off.

[Javi]

Originally Posted by STJ

While helping a friend set up his weight distribution hitch for a new trailer, I noticed his electric break safety cable hanging very low to the ground. I have mine zip tied to the safety chain to prevent this, which I advised him to do the same.
This got me thinking, if the trailer ever did come off the ball when should the safety cable activate the trailer breaks?
Before the trailer reaches the end of the safety chains, or after the chains come off. I would think it should the first option holding the chains never come off.

The SAFETY CHAINS are there to prevent the trailer from getting away... The Break-away should never be tied to the chains..

[flybouy]

The breakaway cable must be attached to the truck and must be short enough to pull the pin if the trailer disengages from the truck. To test that drop the trailer (if a travel trailer) jack so the ball is free. With the chains and cable attached to the truck SLOWLY pull forward until the chains tighten. There should be room eonugh for the trailer tonhue to clear the ball so the chains can support it and the cable should pull the pin out engaging the brakes.

[gearhead]

^Marshall has it right. You don't want the trailer bouncing around behind you constrained only by the chains. You do want the brakes to engage before you run out of chain length.
Having had a U Haul trailer come unhitched, it will be quite the experience no matter what.

[markcee]

The above makes total sense. Our trailer was received from Camping World with the cable quite long, with some of the excess braided through the chains in an attempt to make the two similar in length.

After seeing this post on the proper hookup method, I was curious to see a visual of it being done so found and watched the YouTube video below:

https://www.youtube.com/watch?v=eubR3ssLiOM

In one comment on the video, the viewer stated that the RVIA standard is that the breakaway cable should be longer than the safety chains. Thinking the viewer had something confused, I did a semi-deep dive on this subject and found several other internet references to this RVIA standard.

I have no access to view RVIA standards. Can anyone familiar with this elaborate?

[JRTJH]

Originally Posted by markcee

The above makes total sense. Our trailer was received from Camping World with the cable quite long, with some of the excess braided through the chains in an attempt to make the two similar in length.

After seeing this post on the proper hookup method, I was curious to see a visual of it being done so found and watched the YouTube video below:

In one comment on the video, the viewer stated that the RVIA standard is that the breakaway cable should be longer than the safety chains. Thinking the viewer had something confused, I did a semi-deep dive on this subject and found several other internet references to this RVIA standard.

I have no access to view RVIA standards. Can anyone familiar with this elaborate?

Go back and look at the video one more time. At about 1:25 in the video he says, "If the trailer should become unhooked from the ball, but stay attached to the vehicle by the safety chains, the breakaway cable will activate the trailer brakes to keep the trailer from smashing into the back of your vehicle" and at about 1:45 in the video he states, "The important part is to insure that there is less slack in the cable than there is in the safety chains"

Throughout the video, he states repeatedly that the CORRECT way to adjust the breakaway cable is to insure it is "SHORTER" than the safety chains and he goes on to state that the INCORRECT way is to "weave the cable through the chains because that renders the system totally ineffective" (and the video at that point, shows the breakaway cable that is "clearly longer than the safety chains, which he points out is wrong)....

I didn't see any reference to RVIA standards in the video. In fact, he uses a cargo trailer to demonstrate the system. Cargo trailers are not built to RVIA standards and the RVIA has no influence over anything but RV's (travel trailers, motorhomes, etc).

Where did you see or hear the reference to RVIA standards requiring the breakaway cable be LONGER than the safety chains?????

ADDED: One recommendation in the video that I find incorrect is the "use of a loose knot to shorten the effective length of the cable. That "LOOSE KNOT" can be pulled down the cable and/or vibrate down the cable to lengthen it as you tow. Relying on a "slip knot to stay in one place on a cable" is just not a good idea. You will eventually find the "knot up next to the hitch ball and the cable dragging on the ground"....

[markcee]

Originally Posted by JRTJH

Go back and look at the video one more time. At about 1:25 in the video he says, "If the trailer should become unhooked from the ball, but stay attached to the vehicle by the safety chains, the breakaway cable will activate the trailer brakes to keep the trailer from smashing into the back of your vehicle" and at about 1:45 in the video he states, "The important part is to insure that there is less slack in the cable than there is in the safety chains"

Throughout the video, he states repeatedly that the CORRECT way to adjust the breakaway cable is to insure it is "SHORTER" than the safety chains and he goes on to state that the INCORRECT way is to "weave the cable through the chains because that renders the system totally ineffective" (and the video at that point, shows the breakaway cable that is "clearly longer than the safety chains, which he points out is wrong)....

I didn't see any reference to RVIA standards in the video. In fact, he uses a cargo trailer to demonstrate the system. Cargo trailers are not built to RVIA standards and the RVIA has no influence over anything but RV's (travel trailers, motorhomes, etc).

Where did you see or hear the reference to RVIA standards requiring the breakaway cable be LONGER than the safety chains?????

ADDED: One recommendation in the video that I find incorrect is the "use of a loose knot to shorten the effective length of the cable. That "LOOSE KNOT" can be pulled down the cable and/or vibrate down the cable to lengthen it as you tow. Relying on a "slip knot to stay in one place on a cable" is just not a good idea. You will eventually find the "knot up next to the hitch ball and the cable dragging on the ground"....

Thanks John. I agree completely with your post. Also read your reply on this same subject from a few days ago.

But, I did not say the video states anything about the RVIA standard, a commenter to the video stated this. That is what got me to do a bit of Googling on the subject, where I found other references to this standard. Including an 'expert' reply to a question at eTrailer.com.

https://www.etrailer.com/question-144074.html

I am not contradicting that the breakaway should be shorter than the chains. Just curious what this mysterious RVIA standard is all about. I'm thinking it may be something misconstrued.

[JRTJH]

Originally Posted by markcee

...

I am not contradicting that the breakaway should be shorter than the chains. Just curious what this mysterious RVIA standard is all about. I'm thinking it may be something misconstrued.

I've seen that e-trailer post through the years and have no idea where they or RVIA get the information to support that statement. There is a DOT requirement that pintle hooks (in commercial transportation) be connected with a breakaway cable to activate the air brakes if the safety chains fail. That would occur AFTER the trailer separates from the tractor/semi and is no longer attached.

There is a forum discussion dating way back to 2012 about this topic. So, in the past 9 years it's not yet resolved... Like the GM/Ford/RAM issue, I suppose it will likely not be resolved in the next 9 years either....

You can read that thread here: https://www.keystoneforums.com/forum...ead.php?t=8738 in one of the posts, I link to the University of Tennessee Engineering Department. That link is no longer active, but the quote from that source is in post #7 of the thread. It's "ancient information" but still relevant to the discussion....

[Weldon]

My breakaway was dragging on the ground as well. I had previously posted that I, too, ziptied the "extra" to the chains, but I was mistaken. I zipped the metal dog tags that attached to my chains because they were dragging and the sound of aluminum dog tags hitting the road was annoying.

Anyway, this weekend i swapped my old breakaway cable for this one. I measured my cable first, then ordered. Took maybe 30 seconds to replace. I bought the 4' version. Doubt I'll ever need a 2nd one, but I may be able to help a fellow camper one day. Ignore the sideways pics. I'll figure that out one year (maybe).

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[dutchmensport]

Interesting topic. When I had travel trailers, I always kept the break-away cable shorter than the chains.

I had one come apart once. It just frayed. I replaced it with a spring type one, you know, all coiled up like a spring. Well, that didn't work very well. The tension on the coil kept pulling the break-away pin. Not good. So, I threw that one away and went back to a straight cable.

So, now I have a fifth wheel that also requires a break-away cable, and I still don't know how long the cable should be on it. However, if there is separation, I don't think it matters since fifth wheels don't have safety chains anyway. The pin will pull, the trailer will fall off the back of the truck and the trailer will go flying in an unknown direction! BUT those trailer brakes will lock up!

[STJ]

Thanks for all Great advice I will be making sure my breakaway cable is shorter than the safety chains before the next trip.

[JRTJH]

Originally Posted by dutchmensport

Interesting topic. When I had travel trailers, I always kept the break-away cable shorter than the chains.

I had one come apart once. It just frayed. I replaced it with a spring type one, you know, all coiled up like a spring. Well, that didn't work very well. The tension on the coil kept pulling the break-away pin. Not good. So, I threw that one away and went back to a straight cable.

So, now I have a fifth wheel that also requires a break-away cable, and I still don't know how long the cable should be on it. However, if there is separation, I don't think it matters since fifth wheels don't have safety chains anyway. The pin will pull, the trailer will fall off the back of the truck and the trailer will go flying in an unknown direction! BUT those trailer brakes will lock up!

David,

Here's something you might not have considered. If not, then maybe rethink the situation....

Let's set up a fifth wheel separation and analyze it.

You're towing at 60MPH and hit a rise in the road causing the trailer to "buck and separate from the hitch".....

As the trailer "wobbles in the bed" what do you do? If you apply the tow vehicle brakes, the trailer might "jump the hitch and the pinbox could crash into the cab injuring anyone in the back seat"....

If you apply the trailer brakes, they'll slow the trailer "only until the 7 pin connector separates at which time the trailer is "on its own". If the tail gate bends, the trailer will leave the vehicle and hopefully the breakaway cable will activate the trailer brakes, slowing the trailer as it rolls down the highway, "unguided and unsteered"....

OK, Now let's look at a couple of "what if's"...

What if, as the trailer uncouples from the hitch, the pinbox cuts the 7 pin umbilical or pulls it out of the truck connector? If that happens, squeezing the brake controller won't have any effect on the trailer and IF you try to slow down, the trailer might "jump the hitch and injure you"... If the tailgate holds, you've got a "runaway trailer" bouncing around in your truck bed with NO BRAKES....

Now, let's look at that breakaway cable length....

If the breakaway cable were attached to the front of the hitch and cut to a length where it would pull the pin, activating the trailer brakes as the kingpin backs out of the hitch, then no matter what happens to the umbilical connector, the trailer will have active braking and start to slow, hopefully eliminating the possibility of jumping the hitch if you take your foot off the accelerator.... If the tailgate holds, the trailer brakes will (hopefully) keep the trailer kingpin "riding on the tailgate lip" as you slow the truck... If the tailgate bends or if the trailer jumps the tailgate, it'll be actively braking with the emergency brake system and not "pushing the truck as you try to slow down.....

Granted, there are a couple of "what if's" that could affect the above situation, but IMHO, if you shorten the breakaway cable so the trailer brakes activate "as soon as the kingpin separates" you'll have a better chance of the trailer not entering your cab and not "freewheeling" around in your truck bed until you can get it stopped or until it jumps the tailgate and hopefully the breakaway cable finally activates the trailer brakes.....

The above is probably a "worst case situation" that none of us will ever face, but "what if it happens" ???

Think about how long your breakaway cable is and what would occur "IF" the worst happens to you.

[rlh1957]

Breakaway cable should be protected from snagging anything or binding when turning.
Even if protected many people have to much slack in them.
You want that cable to disconnect and brakes to engage as soon as tongue comes unhitched, not after trailer and chains are 13 inches behind you.

I prefer connecting the disconnect hook to another solid point on the TV.

If a chain disconnects... there gores your disconnect cable attached to it.
I separately attach the disconnect cable separately to the hitch.
On my fifth wheel I even have a point on the truck to attach too separate from chains and separate from the hitch.
But thats just me.

[Mainer]

I have a LOOSE zip tie around the umbilical cord and the breakaway cable. It gets attached to the top of the coupler with the padlock on the latch. Breakaway cable snaps to an eye bolt just above the bumper with 2-3 inches slack. Both cables are kept away from pinch or snag points and turns don't change the amount of slack so brakes will activate before trailer is on the chains. Dad did that with string before Zip ties were invented.