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Old 05-27-2016, 03:39 PM   #1
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CAUTION!!: Double Check Trailer Hitch

We spend lots of time traveling in our Challenger. Had a very serious problem come up after picking up our coach at Thor's Wakurusa Factory Service location.

I stopped to get fuel, walked behind my more coach to add fuel and my towbar was literally on the pavement at the forward portion of the hitch. Initially, I thought the Reese hitch had failed. Wrong. What happened was the frame where the hitch was attached had split on both sides.

Our hitch is rated at 5000 lbs. Our Ford Explorer's curb weight is 4600 lbs. Again though - it was NOT the hitch that failed - it was the coach frame chassis.

As of today, Thor has been very supportive in helping get the problem fixed. I found this problem on Tuesday, May 24. Since my initial phone call, I have talked with Thor, Morryde and Ford. Obviously, I am concerned with fixing the problem but just as concerned with WHY this happened. Poor design, weak chassis, other engineering related issues or is this a simple 1 off non-standard problem. Good news/bad news - Morryde has a fix for the problem but locally applied it is more than $1300 to apply. More good news/bad news. Morryde will apply the fix BUT I must travel back to Elkhard - 275 miles north of me.

The main reason for me posting this is to alert other owners with toads - CHECK YOUR HITCH AND FRAME!!!!

I will continue to update as I get more info.
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Old 05-27-2016, 04:05 PM   #2
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That looks to me like a bad weld, or they just tacked it on and forgot to complete the weld.

Especially with all that rust there; its been hanging like that for some time (or there has been an air gap there for some time).
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Old 05-27-2016, 04:12 PM   #3
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JamieGeek. You are correct it is rusted indicating a the split has been there for a while. But it is not welded to the frame. The Reese hitch is bolted to the frame chassis. The chassis is a single solid piece (or it was before it split). This split is the largest concern. While it maybe a non-standard 1 off problem, it could also indicate a number of other issues to include poor engineering/design.
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Old 05-27-2016, 04:26 PM   #4
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Glad you caught it when you did!!
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Old 05-27-2016, 04:32 PM   #5
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KC - wow right on point. When you think of all that could have gone so tragically wrong. A few hundred $s to fix the problem is amazingly blessed.
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Old 05-27-2016, 04:37 PM   #6
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The good news is that Morryde is actively working with us to understand what happened and repair.

We'll update on all of it.
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Old 05-27-2016, 05:18 PM   #7
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Quote:
Originally Posted by bigben View Post
....cut.... Poor design, weak chassis, other engineering related issues or is this a simple 1 off non-standard problem. ....cut.....
I've read of these types of chassis failures before, so it's not a one-of-a-kind problem.

I can't honestly tell what's going on from the picture, but know than on many larger motorhomes (many smaller ones too) there is a chassis extension welded onto the original vehicle chassis. On most motorhomes I've looked at the hitch receiver was bolted to an extension, not the original Ford frame.

The picture doesn't make it clear (to me at least) whether the failure is on added frame extension, or whether that's part of original frame "C" channel. I expect it's on the added extension because of the shape, and also the size of your rig.
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Old 05-27-2016, 05:37 PM   #8
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Chance - yep. It is an extension. Working now to understand what happened. I spent my 2nd career after the US Army in manufacturing and have a working understanding of design and specs. I've seen the perfect storm before where everything is within specs but a failure still happens. Want to make sure others do a physical inspection of the hitch to avoid what could have been a real catastrophe.
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Old 05-27-2016, 05:55 PM   #9
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Originally Posted by bigben View Post
Chance - yep. It is an extension. Working now to understand what happened. I spent my 2nd career after the US Army in manufacturing and have a working understanding of design and specs. I've seen the perfect storm before where everything is within specs but a failure still happens. Want to make sure others do a physical inspection of the hitch to avoid what could have been a real catastrophe.
Thanks for letting everyone know. There is nothing more important than safety as far as I'm concerned.

As an engineer I can take an educated guess. First I need to ask, to get your tow bar level, do you use a hitch ball mount with drop? If so, how much?
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Old 05-27-2016, 06:19 PM   #10
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For reference this is one with 10-inch drop.
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Old 05-27-2016, 06:26 PM   #11
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Our Axis has a Reese hitch bolted to (6 bolts, 3 each side) an approx 36" frame extension that is held to the frame also with 6 bolts (3 each side). The bumper is also bolted to this extension and the two "skid bars" are welded to it. Everything looks pretty solid (If I had an issue I think I would have found out last year when I pulled a car with it for 2000+ miles.)
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Old 05-27-2016, 07:34 PM   #12
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looks to me like it was a failed welded joint. I can see what looks like the weldment (fillet weld).

I'd probably push hard to get them to cover a local repair. Any good certified welder could do an acceptable repair....
BUT
there may be some benefit to making the drive and let them do it
future liability
and as a safety to other owners, for them to be fully aware and responsible for the repair, and failure.... who knows, it might end up being a recall situation....
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Old 05-27-2016, 07:43 PM   #13
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WOW, I will be defiantly looking at mine today!!!!!
Thank you for the posting.
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Old 05-27-2016, 09:25 PM   #14
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Quote:
Originally Posted by JamieGeek View Post
Our Axis has a Reese hitch bolted to (6 bolts, 3 each side) an approx 36" frame extension that is held to the frame also with 6 bolts (3 each side). The bumper is also bolted to this extension and the two "skid bars" are welded to it. Everything looks pretty solid (If I had an issue I think I would have found out last year when I pulled a car with it for 2000+ miles.)
Is your Reese hitch similar to what appears on picture? Can't tell for certain from picture because it's cut off. I'm curious if the longitudinal (front to back) hitch arms on each side where the 3 bolts are that attach to motorhome is relatively short.

From the way the lower flange is bent after it failed, it looks like receiver may be something like 8 inches long front-to-back along frame extension.
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Old 05-28-2016, 12:43 AM   #15
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Thanks for the heads up!!


When I get home I am taking my Vegas to a friend that is certified Navy welder and have him go over each and every weld on the RV (a steak on the grill and a few brewskies and we will be even).


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Old 05-28-2016, 11:56 AM   #16
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Caution Update

I want to make sure everyone knows why I've posted this. I believe this is such a safety issue and with the cause still being determined, fellow owners ought to visually check the hitch attachment.

My hitch is a standard Reese 5K hitch. It is the bolt on type (3 bolts on each side). What failed is the frame extension where the hitch is attached. These is no weld here, rather the frame is a standard formed channel type. I pull a 2013 Ford Explorer with a curb weight of approximately 4600. In the past 13 months we have traveled more 18,000 while towing our Explorer. I have a 2" drop on the hitch to more correctly align the hitch with tow points on the Explorer. I say all of this to make sure there is context for use and/or cause of the failure.

Thus far, Thor and their supplier Morryde have been all over this. The good news there is an answer for the repair. The bad news - still not sure why the failure.

I will continue to post updates as I move through this in the next few days.

I am attaching a copy of the current hitch since this failure occurred.
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Old 05-28-2016, 01:49 PM   #17
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Not an engineer but I can see that there will be a LOT of stress on the metal in the the area where it failed. Throw in a drop hitch for increased leverage and maybe a weak or failed toad braking system and there will be a trementous amount of stress every time you stop or make sharp turns. Baring a recall or specific instructions from Thor - perodic visual inspection is mandatory. For the first time I am questioning the use of NSA braking systems especially with heavier toads. I would look for Morride to add two more holes and hitch mfg. adding a piece of angle for a cheap fix in future builds.
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Old 05-28-2016, 03:33 PM   #18
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Quote:
Originally Posted by bigben View Post


....cut.... The bad news - still not sure why the failure. ....cut....
The Devil is in the details, and in this case I see a few that came together -- mostly due to poor design and fabrication.

I can't be certain from a picture, but I can give you an engineering opinion of likely cause(s):

1) Brake systems may help stop the car, but a time delay of even fractions of seconds will allow very high forces to be transmitted forward momentarily through tow bar. Based on motorhome being much heavier than toad, the braking force on a sudden stop (regardless of speed -- can be at 10 MPH) could easily reach 3,000 pounds in your case.

2) That force, acting through a lever (moment arm) from hitch ball to frame attachment bolts, will obviously try to rotate the Reese hitch clockwise (as seen from driver's side of motorhome). The greater the drop the worse this becomes. Your 2-inch drop isn't much, and even if it was a lot more drop, the frame extension should have been designed to take it.

3) It's hard to confirm from picture, but it looks to me that one of the biggest issues is the way the extension was made. The 90 degree bend/curve appears too sharp, adding a stress concentration point. The correct way is to have a smooth radius bend similar to a Ford chassis or as can be seen on the Reese hitch on the first picture. If they formed this on a brake (which is possible, maybe even likely) there may be a scoring line that makes stress concentration even higher, and helps the tearing away of the flange to start.

4) The Reeese hitch itself looks short along the frame extension. The shorter it is, the higher the stresses on the frame extension. The shorter length will create additional downward forces at the rear bolts which pulled the flange away.

5) If the frame extension was a little longer beyond the hitch, it would reduce stresses at the point of failure. This alone shouldn't be necessary but contributes to the cumulative loads that increase stress at failure.


Again, it's difficult to say from a picture, but I think all these came together to exceed the frame extension's capacity. Just my 2 cents... which is all it's worth.
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Old 05-28-2016, 07:24 PM   #19
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Sorry for your problem but very happy you found it when you did. Thanks so much for advising us of this issue. I'm sure a lot of people will be checking their hitch as i just did. Please continue to update us.

John & Diane
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Old 05-28-2016, 08:52 PM   #20
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Ben,

For curiosity sake, how many miles do you have on the coach towing?
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