Nut backed off ball caused accident

[iamalienru]

I was heading up to santa cruz ca. in my 40' american eagle I had my motorcycle in tow on a utility trailer. Before I left I had tighten the nut on the ball with an air impact driver the kind that you take lug nuts off a car or truck it was tight lock washer in place. safety chain hooked up all was good. traveling down the 101 near north Hollywood ca. I saw the trailer jumping in my rear camera as I slowed the trailer let loose breaking the safety chain and hitting another car. what a mess. I have never had this happen before but the nut from the ball was laying there on the freeway. now I am having insurance issues on the trailer and coach it was the vacation from hell and it's not over. The only type of ball I will use from now on is one with a cotter pin going through the bottom of the shaft. Uhaul carries them. Sorry for the sad story but i hope this will help others. I still do not understand why that nut backed off

[hammer21661]

Tighten with a torque wrench or a breaker bar with a pipe you didn't get it tight enough with your little impact wrench. The take a steel chisel and a hammer strike the threads with the chisel. One hit on each side directly under the nut will do it. Periodically check the nut but the boogered up threads will keep it from coming off again. Now if you ever need to take it off yo can either use a pipe wrench (sometimes you can use an adjustable)to hold the top or file the thread so the nut can pass.

[Old-Biscuit]

SDcampowneroperator wrote:
Sorry to read of your trouble. Next time weld the ball on, or the nut to the threads. Been doing it for years. After all, when does anyone change the ball? Even if they did need to, a grinder will cut out the weld.
Nuts will come loose if the hole in the mount is bigger than the ball stem no matter how well torqued. Could that be the cause?

Seen that problem more than once....

As suggested....good tack weld on nut/threads after properly torqued.

[loulou57]

We were just talking to our friend the same thing happened to him, luckily there was no damage to his TV or 32' TT. It happened as he was just pulling into his CS.

[nevadanick]

Read his post, he had a lock washer.

[Supercharged]

lock washer, hello

[Lowsuv]

In 41 years of towing I have never had a ball come loose .
And I have not really done anything special to tighten them .
I have a 40 year old ( old style ) torque wrench that I use to tighten stuff only because it is the longest lever in my 1 /2" drive socket set .
all of them have the standard lock nut washer .
however, I have 4 stingers , plus my airlift hitch , each of which the ball has been in place for years . Once they're on they stay put .
Sorry for your accident , it could have happened to many of us .

[Vulcaneer]

iamalienru wrote:
the trailer let loose breaking the safety chain

Not only was the nut not secured properly. It sounds like the safety chains were below spec, too long, or not crossed. There is no reason why a trailer should break proper safety chains if they are crossed. The tongue nestles safely in the cross, and keeps the tongue from digging into the pavement. When that happens the tongue will break safety chains, or the hitch. That is why you cross safety chains.

[Turtle_n_Peeps]

iamalienru wrote:
I still do not understand why that nut backed off

Sorry for your troubles but I know exactly why the nut backed off.

I have a really nice 1/2" impact gun and a 2 stage air compressor so I can really jack up the pressure when needed. It won't back off some headbolts rated at 120 to 150 ft/lbs of torque.

The stud you have on your ball is like 400 to 500 ft/lbs of torque.

Sorry, but you weren't even close to getting enough torque on the stud.

[midnightsadie]

hope things work out,glad no body hurt, and learn, I,m gonna go recheck mine in the morning. thanks for the post ,you might have saved some lives.

[352]

If you use a pipe wrench or a crescent wrench a 4 foot helper bar and lean into it you will never ever have a loose nut on your ball.
nuff said

[WyoTraveler]

Tip the hitch sideways and slide it into the receiver. You don't even need a torque wrench. calculate your weight and length of pipe breaker bar you need and stand on it. 3/4" nut 160 pounds, 1" nut 250 pounds, 1 1/4" nut 450 pounds ft pounds. I personally wouldn't trust any air wrench for torque.

[VintageRacer]

That's why the instructions that come with the ball say to tighten the nut with a torque wrench, not an impact wrench. Totally your fault. Surprised you admit using an impact wrench on that. You have no idea of what torque you are developing with an impact wrench. Depending on the ball size the correct torque is up to 450 ft lbs.

[SDcampowneroper]

Sorry to read of your trouble. Next time weld the ball on, or the nut to the threads. Been doing it for years. After all, when does anyone change the ball? Even if they did need to, a grinder will cut out the weld.
Nuts will come loose if the hole in the mount is bigger than the ball stem no matter how well torqued. Could that be the cause?

[path1]

Yep, cotter pin with ball threads, better known as a "Jesus clip" keeps you out of trouble. Or just drill your own, cheap insurance
http://www.uhaul.com/MovingSupplies/Hitch-balls-mounts/Hitch-balls/2-Hitch-Ball-2-3-16-Shank-Length?...

Here is a close up of a cotter pin in threads, if any folks never seen one before. See the pin in the threads? Nut can't back off or maybe I should say a lot harder to come off. Cheapest insurance you'll ever find.http://www.omninerd.com/assets/content/2/4_article_131_full_installed_hitch.jpg

[BenK]

What is your impact gun rated for?

At what PSI?

They do lose torque capacity over time...how old and how well maintained or used is it?

Without a torque wrench or some such, calibrated tool...no one knows what the
torque was on that nut.

What is the torque required on that ball/nut? The info is on the label/package/etc
it came in

Another thread on this topic here at this link: How often do you need to tighen your hitch ball?