Breakaway cable length?

[oceantribe]

I made a rookie move, unhitched on a slight slope with only one wheel double chocked. The safety chains were still attached so the trailer stopped
swinging in short order... but the eye of the breakaway cable at the hook end
pulled out (did not pull the switch for the brake), we were on a trip so tied
a bowline and taped it up. Now I want to replace the cable (i know what the original length is) but, is there a rule of thumb for the ratio between the chain and the cable? I just bought a smaller Nissan 4x4 to tow the BaseCamp and the chains/cable dangle closer to the ground and considering shortening them for rough terrain.

[RickDavis]

While somewhat debated, I am of the feeling that the cable needs to be long enough to not pull out until the trailer has completely seperated from the tow vehicle, meaning safety chains broken also. The cable should NOT be attached to the hitch, but instead elsewhere on the vehicle.

If your chains are crossed and something happens the tongue should drop onto the chains and allow you to make a safe stop. It is not desirable to have the brakes come full on if this happens.
I loop my excess cable with a tie wrap. The loop will pull out under stress

Fortunately I have never put any of this to th test in the real world

[Melody Ranch]

You want the brakes to be applied if the trailer becomes un-hitched...not after the chains would break away. You would want the brakes to be applied while the chains were still giving you safety attachment.

[JFScheck]

Get those brakes engaged upon seperation so the trailer doesn't run into the tow vehicle, the chains will keep the nose from digging in but you don't want it running up under the tow vehicle - especially if you are heading downhill...

[RickDavis]

Originally Posted by JFScheck

Get those brakes engaged upon seperation so the trailer doesn't run into the tow vehicle, the chains will keep the nose from digging in but you don't want it running up under the tow vehicle - especially if you are heading downhill...

I think that is why there is debate.
In my mind the purpose of break away is just that. You do not want a situation where the brakes Lock and slam the trailer against the chains. Particularly going uphill. If going downhill the trailer will only go under the tv a short way, being stopped by the jack post and a controlled stop should still be possible as long as the umbilical cord is still attached.

The real purpose of the breakaway is to stop the trailer as quickly as possible if it becomes separated from the TV to protect Those near you.

This has been much debated over the years.. The Current WBCCI safety guy agrees with me on this question but before his time the previous guy recommended a short cable.
There is probably some validity to both arguments.
If the brakes were to come on gently instead of full on I would probably move into the other camp

Just to muddy the debate more, There are NO safety chains on 5th wheel trailers, only a breakaway switch

[Pahaska]

I am in the longer cable camp. I don't want full trailer brakes applied unless the trailer is fully disengaged from the tow vehicle.

[SteveH]

Originally Posted by Pahaska

I am in the longer cable camp. I don't want full trailer brakes applied unless the trailer is fully disengaged from the tow vehicle.

That's me too.

[Melody Ranch]

I agree with you Guys on this....basically. However, I don't want a free wheeling Airstream, still attached to the truck by chains, and no way of applying brakes to keep it back away from the vehicle. This is where the hook up acts as a system....the length of the break away for the brakes, the length of the electrical umbilical and the length of the chains. I guess the length of the break away should be long enough to activate only when the length of the umbilical is exceeded and you loose manual brake control.

[dznf0g]

Originally Posted by Melody Ranch

I agree with you Guys on this....basically. However, I don't want a free wheeling Airstream, still attached to the truck by chains, and no way of applying brakes to keep it back away from the vehicle. This is where the hook up acts as a system....the length of the break away for the brakes, the length of the electrical umbilical and the length of the chains. I guess the length of the break away should be long enough to activate only when the length of the umbilical is exceeded and you loose manual brake control.

Utilize the manual switch on the controller lightly to create tension on the chains and roll slowly to a stop.

[JFScheck]

Originally Posted by dznf0g

Utilize the manual switch on the controller lightly to create tension on the chains and roll slowly to a stop.

I'm gonna assume that if the trailer has fallen off of the hitch and is being supported by the chains that there may also be a good chance the brake controller is no longer hooked up to the trailer...

IF IT DID NOT - then I too would manually slow the trailer down and pull over.....

And WoW - I did not know that the 5th wheelers had no type of chain!

[dznf0g]

Originally Posted by JFScheck

I'm gonna assume that if the trailer has fallen off of the hitch and is being supported by the chains that there may also be a good chance the brake controller is no longer hooked up to the trailer...

IF IT DID NOT - then I too would manually slow the trailer down and pull over.....

And WoW - I did not know that the 5th wheelers had no type of chain!

My umbilical is plenty long enough to stay connected if the tongue falls to the chains. I am always careful to route it so there would be a minimum of fouling if something happened. I guess, if it did come out, I would suggest (like in most emergency situations) don't panic and hit the brakes. I would suggest coasting to a stop or lightly applying TV brakes.
The worst that can happen, if you keep your head is a damaged bumper, tailgate, maybe a jack, coupler latch and bottle cover. Considering the potential alternative, that's cheap.

[noreen&sal]

Originally Posted by dznf0g

My umbilical is plenty long enough to stay connected if the tongue falls to the chains. I am always careful to route it so there would be a minimum of fouling if something happened. I guess, if it did come out, I would suggest (like in most emergency situations) don't panic and hit the brakes. I would suggest coasting to a stop or lightly applying TV brakes.
The worst that can happen, if you keep your head is a damaged bumper, tailgate, maybe a jack, coupler latch and bottle cover. Considering the potential alternative, that's cheap.

DITTO. Sal.

[RickDavis]

On the brighter side, I worked for a transporter for a number of years towing new units to dealers. This gave me an opportunity to talk with lots of drivers with many hundreds of thousands of towing miles behind them.. I have never met anyone who had suffered a trailer separation so it does not happen very often.
Regardless of what length you make the cable, check every now and then that it will work when pulled.
What I have seen a few times is someone hook up a fifth wheel and trap the break away cable between the hitch plates. The first time they made a sharp turn the cable would pull and lock the brakes