Blue Ox tow bar fail

[Guest Ray Davis]

Inspect your tow bars.          https://www.irv2.com/forums/f278/tow-bar-failure-527783.html

[Dennis H]

20 pages of reading and it's still early.....Thanks Ray, every day we need a reminder to check things we take for granted only too often .... Dennis

[PeterSchweizer]

For me I prefer an independent tood brake system from my coach. So when there is a bar and saftey cable failure  the emergency switch is activated using the toods brakes. I use the Roadmaster invisabrake which has an independent compressor n cylinder that pulls a cable on the toods brake peddle.  There are other portable power packs that do the same by pushing on the peddle and they are portable so can be used on another vehicle. The invisabrake is activated by sencing an independent 12 vdc signals from each of the left n right brake lights wiring and progressively activates the toods brakes, so it not just an immediate standing on the brake peddle.

I do not agree that the emergency disconnect cable should be shorter than safety cable because its intent is to stop the tood after complete separation from tow vehicle. 

Just think going down the road pulling with your 400 HP Diesel the tood brakes activate you might not sence it n omly know when a passing vehicle is blowing their horn n pointing so you end up with 4 blown tires n shaved off rims maybe ever the rotors too! Remember the stories about someone leaving the toods parking brake on driving some distance before realizing the burned up 4 tires n rims. Now I was lucky I caught that someone left it park after hookup in  the first few feet of driving away- as others here have. However we all have seen the photos n stories of others.

Also if emergency cable n safety cable are intact after tow bar failure and the tail light wire harness is longer (n not tied to tow bar) you may still be able to tap coaches brakes, n slow down tood safley to a stop if you have systems mentioned above.

[Gary 05 AMB DST]

I replied on the RV2 site.  #280

 

Gary 05 AMB DST 

[Guest Ray Davis]

 Then there's the guy that when they finally stopped he was just dragging the whole front end of his toad,  pulled it right off.     

 I nearly bought a Blue Ox, they look really good, and I like the rubber bellows but my Roadmaster seemed a little beefier to me.                                                                     I use a Brakemaster made by Roadmaster that has a little air reservoir tank but the small compressor is probably a better idea.

[Chargerman]

I wasn’t confident with the construction of my Blue Ox towing my 6500lb pickup so I purchased a NSA Hurcules tow bar rated at 12,000lbs. Been very happy with it. It it very stout and it has a lifetime warranty. 

[Poohbear]

39 minutes ago, Chargerman said:

I wasn’t confident with the construction of my Blue Ox towing my 6500lb pickup so I purchased a NSA Hurcules tow bar rated at 12,000lbs. Been very happy with it. It it very stout and it has a lifetime warranty. 

Would agree I like the nsa products and customer service is great.

[Dr4Film]

Personally regardless of what the iRV2.com OP posted, my opinion is that his bar had been under some stress at one time or another and the metal had fatigued in the area where it had cracked and broke. There are some photos near the end of the thread that substantiates this theory.

What I find astounding is that the iRV2.com thread has 21 pages and growing.

I use an older model Adventa LX 10,000 lb Blue Ox Tow-bar which is a class IV bar with 5000 lb cables. Never come close to mistreating the tow bar and other than a good paint job it still looks as good as the day I purchased it second hand.

I tow a 2006 Saturn Vue.

[Bobbyboy]

I looked at the picture and am still trying to figure out where the failure occurred.  Was it where the tow bar is attached to the tow vehicle or where the bar is attached to the swivel (ball) at the coach end.

 

[Chargerman]

The two plates that broke away are welded to another part and that part goes into the receiver of the Coach. 

[Dr4Film]

I have attached a photo of a new Blue Oz Avail Tow Bar,

The photo is looking from the two tow bars toward the hitch with the tow bar right side up

The OP's photo ( which is a pretty piss-poor depiction) is looking from the hitch side toward the two tow bars but he took the photo with the tow bar upside-down.

I have re-positioned his photo with the tow bar  turned right side up.

Edited March 22, 2021 by Dr4Film

[Bobbyboy]

Thanks. I have the BO Aventa LX. 10000lbs which is different from the one pictured

[Dr4Film]

36 minutes ago, Bobbyboy said:

Thanks. I have the BO Aventa LX. 10000lbs which is different from the one pictured

I use the same one as you. Nothing to worry about as long as you don't try to do anything stupid with it. If you treat it correctly it will serve you well for many years. I bought mine in 2010 but didn't really use it much as I was towing a 30 foot trailer 99% of the time. I would only use the tow bar to make some side trips when in Alaska and Florida. I have now been using the tow bar since buying the winter house in 2016 and selling the trailer in 2018. Even though I purchase it secondhand it has a lot of life left in it. One of these years when passing IA I will stop at the Blue Ox factory and have them go over it. No plans to switch it out as it sits at the back end of my coach all the time just waiting to be used.

[96 EVO]

I have pulled a car for many miles with the brakes on, after the 'tech' installing an AF1 system in my towed, screwed a long self tapping screw into the cars brake booster.

Car has front disc's, rear drum's. Disc's were glowing in the dark, but never caught fire. 

Cost his employer about $5G. 

Rear, entire brake system, front, right down to the spindles!

[amphi_sc]

Besides tow bars, don't forget to check how solid the base plate is.  This was the view of car once we removed the front plastic to investigate a little looseness.  Always check all attachment points for any unusual feel. 

And when going down the road, please check your rear camera!!! In a different instance from a couple years prior, I know of one case where one arm of the tow bar broke and the car banged the rear of the coach from side to side for well over 50 miles before the driver paid any attention.  (Two lane Alaska roads where vehicles following could not get driver's attention flashing lights/blowing horn nor safely pull beside nor pass.  No cell service to call either.  Vehicles following finally gave up.  Hard to believe it wasn't felt nor visible from the side mirrors. It was amazing to see how well the one remaining arm stayed attached throughout all the damage.)

And I've seen emergency brakes left on or vehicle in park (luckily dragging across the dirt), but stopped those drivers before they left the park.  And satellite dishes and bat wings up.  And a door awning out on a rainy day.

Always inspect before pressing the D button (including lights), check for wheels turning, and tow bar arms not collapsing when applying the brakes in the first 50 feet or less.  If you use a dolly, check the tie downs as the load may shift or settle after a couple of turns.

Just had my Roadmaster tow bar inspected by the Roadmaster service team at Perry GA and got a thumbs up, but I will still look it over each time.

FWIW

[Moonwink]

I still don't understand exactly which part failed looking at the picture.  DR4Film posted the picture upside down.  The original image was laying on it's left side (see the car tire in the background).

 

Below is an exploded view of an Aventa II Tow Bar.  The image above doesn't look like it was the Aventa model though.  I suspect the two plates were welded to the 2 inch box going into the receiver and that was the point of failure.  #7 in the view below was not welded but the picture appears to be #11 with the two plates on either side.  The two arms connect to #11.

 

[mandms59]

1 hour ago, Moonwink said:

I still don't understand exactly which part failed looking at the picture.  DR4Film posted the picture upside down.  The original image was laying on it's left side (see the car tire in the background).

 

Below is an exploded view of an Aventa II Tow Bar.  The image above doesn't look like it was the Aventa model though.  I suspect the two plates were welded to the 2 inch box going into the receiver and that was the point of failure.  #7 in the view below was not welded but the picture appears to be #11 with the two plates on either side.  The two arms connect to #11.

 

 

The Tow bar that failed is an Avail.   The part the failed would be the yoke #7 in your schematic.  The updated Avail design uses two plates welded to the side rather than the U channel type (was actually 2  L's welded vertically together) the two loose pieces on each side is whats left of the yoke.   See Dr4Film's previous photo for new design.

Edited March 23, 2021 by mandms59

[Dr4Film]

Moonwink, you are looking at the photo from the wrong perspective. That's exactly why I attempted to put the OP's photo back in the correct orientation for people to better understand. His photo was taken with the tow bar laying upside-down NOT right side up as it should have been taken.

First off, his tow bar is not an Aventa II but rather the Avail for a 2 inch hitch. The part that failed is the shaft that slides into the hitch and it broke right at where the #4 arrow is pointing to on your Aventa II diagrams.

[Moonwink]

Now that the towbar has been identified, here's a picture of what it looked like:

It's a shame those welds broke.  The more I look at the critical parts, that single bolt allowing the bar to twist looks like the weak link in the chain.  I think I like the design of the Aventa II I have better but it still relies on the strength of  a single 3/4" bolt to pull the towed.  Seems like 10,000 lbs is a lot of weight for one 3/4" grade 5 bolt. 

 

Edited March 23, 2021 by Moonwink

[Chargerman]

Many tow bars utilize a bolt to provide a pivot point. In this case the bolt was not the cause of failure and rarely is. In the case of this failure it was the metal component that failed due to fatigue or stress

[Dennis H]

IMO, it's still not clear as to what failed. It appears the two ears broke off. Those two ears simply provide support for the tow bar when it's in the stowed position. They would have zero impact when the tow bar is deployed. From the pictures posted on the other site, it appears the failure occurred inside the tow apparatus itself. One picture shows only the 2" bar in place with the rest missing. Too much misinformation which produces too much speculation. In order to make an intelligent assessment, IMO, one needs to have pictures which show the entire bar, then some closeups of the damaged/failed area. With the information provided I believe it's imperative that we simply check OUR equipment and ensure what WE are using is safe and operable. We are also ASSUMING the failed equipment was NEVER stressed or compromised in any fashion. I know I buried mine one time when the roadway failed as I was attempting a u-turn because a bridge was washed out. This worried me until I was able to have the tow bar checked by a professional and given a green light as to it's worthiness. Remember, safety first, for you, your family and those with whom we share the road.....Dennis

Edited March 24, 2021 by Dennis H
Spelling correction

[Dr4Film]

Dennis, the raised tabs are still attached. It broke somewhere just before the raised tabs.

Hard to tell exactly due to the OP's crappy photo.

[Moonwink]

Borrowing a picture from the IRV2 post, we see more detail here showing how the towbar "broke".  The welds didn't fail after all.  Clearly, the tabs were torn off the 2" receiver bar.  Many of the images below are borrowed from IRV2.

The person that posted this image thinks he can see rust (the red arrows) where the metal had been cracked before it sheared off (the green arrows).  I've blown up his picture to try to see what he says is there.  Comparing the picture above with the one below, it's hard for me to recognize them as the same towbar.

The arrows show the point were the metal was sheared off.  The weld to the 2" box held.  To me, this indicates there was tremendous stress put on that metal that caused it to shear off like it did.  It appears both sides were sheared off cleanly.  The question that still remains is which direction did that stress come from?  The metal isn't twisted like would happen if it was twisted sideways.  It's more like the stress came straight up or down on the point of failure.  It appears later models of the Avail towbars had the pieces that sheared off welded to the side of the 2" box instead of forming a U and welding it to the end of the 2" box.  I suspect baking up without disconnecting had something to do with this failure.

 

 

 

Edited March 24, 2021 by Moonwink

[Dennis H]

Looking at all the pictures gives a better understanding of what 'broke'. While it is impossible for us to determine why, I would offer the same conclusion as Moonwink. For those two tabs to "snap" at the same time, at some point in time they suffered severe stress. Only the owner knows when that occurred. It's also possible he isn't even aware he put stress on the tow bar, but it's obvious someone did. If one of the tabs failed, the other would show some twisting before following it's brother. The fact they snapped off in unison suggests the tow bar suffered extreme stress at some point. Rust could also be a factor. Looking at the rest of the poster's equipment suggests some level of neglect. Just my opinion of course.....Dennis

[Dr4Film]

Dennis, I totally agree! I had stated that opinion on my very first post in this thread in contradiction to the OP who posted this on iRV2.com

The only other conclusion would be a severely incompetent and compromised weld was done on this tow bar.

Personally, I think the design and construction of the Avail Tow Bar is not one that I would trust and purchase versus the older Blue Ox Aventa LX Tow Bar that I own.

Both are rated for 10,000 lb. but built entirely different.

Edited March 24, 2021 by Dr4Film