Andersen and Demco

[Jumar]

Like the above poster mentioned, I put a 3" x 1/4" grade 8 bolt through with a nyloc nut on the end and it holds the latch securely down. A few hundred miles with this bolt in place and I have not been able to reproduce it.

The hitch does not pop off when jacking the trailer up while attached to the ball. I did a little more testing while watching my rear camera and driving. It appears when it unlatches, it happens in phases. First it partially unlatches the coupler and then after more bumps it will fully unlatch.

My current working theory is that the spring in the Demco coupler latch is way too weak (possibly an isolated case on my hitch?) and a combination of bumps/jolting it causes the coupler latch to dislocate upward past the ball. It feels like there is very little pressure/force on my hitch latch when going from latched/unlatched state. Is that normal?

If a bump causes the rear end of the truck to go up, and along with it the Demco coupler, the chain tension will disappear. At this moment the ball may not be applying any rear pressure against the coupler latch. Simultaneously, the momentum also carries the coupler latch slightly up from its latched position. When the chains tighten as the rig comes down from the bump, it pulls the ball backwards rapidly and moves the ball under the elevated latch. At this point it either causes it to fully unlatch, or unlatches on the next set of bumps...

[Demco]

Originally Posted by Jumar

Like the above poster mentioned, I put a 3" x 1/4" grade 8 bolt through with a nyloc nut on the end and it holds the latch securely down. A few hundred miles with this bolt in place and I have not been able to reproduce it.

The hitch does not pop off when jacking the trailer up while attached to the ball. I did a little more testing while watching my rear camera and driving. It appears when it unlatches, it happens in phases. First it partially unlatches the coupler and then after more bumps it will fully unlatch.

My current working theory is that the spring in the Demco coupler latch is way too weak (possibly an isolated case on my hitch?) and a combination of bumps/jolting it causes the coupler latch to dislocate upward past the ball. It feels like there is very little pressure/force on my hitch latch when going from latched/unlatched state. Is that normal?

If a bump causes the rear end of the truck to go up, and along with it the Demco coupler, the chain tension will disappear. At this moment the ball may not be applying any rear pressure against the coupler latch. Simultaneously, the momentum also carries the coupler latch slightly up from its latched position. When the chains tighten as the rig comes down from the bump, it pulls the ball backwards rapidly and moves the ball under the elevated latch. At this point it either causes it to fully unlatch, or unlatches on the next set of bumps...

Jumar -

Thanks for in-depth description ! I appreciate it. Couple things that come to mind reading about what you describe. While you are correct the bump that unloads the the chains would also shove the ball into the coupler removing any force of the ball being in contact with the keeper effectively holding the latched closed. That being said the internal spring even if weak only needs to be strong enough to cover the the weight of the handle and internal components if that makes sense? The bump inertia allowing the handle and internals to want to move up is directly offset by the spring pressure. The spring rate is 12lbs per inch and I would estimate that there is an inch of preload. Internal parts may weigh a 1Lb give or take. The other thing to think about is the handle has to be almost all the way vertical before it goes over center and will stay up against the spring pressure, so in thinking about that I don't see a way the coupler can stay partially open with gravity and spring pressure is trying to close it on its own without some other variables helping it do so. Those 2 variables alone should shut the coupler when there is both tongue weight and force pulling on the ball from the tow vehicle.

After reading what you are reporting I'm wondering that if the WD hitch isn't playing a part in this. It is known that the chain tension pulls the hitch ball back against our ball keeper, that doesn't pose a concern in wear or coupler strength but I'm wondering if the force of the chains pulling + plus the rotation of the ball and friction of the ball surface on the keeper is enough to push the coupler open under oscillation? Not knowing exactly how much pressure there is from the WD chains I'm thinking it may be plausible to think the Oscillation+friction could be playing games? One thing to maybe try is to reduce the chain tension on the Andersen and see if the handle quits working its way up or maybe takes longer or bigger bumps to do so.

[Wazbro]

Originally Posted by Jumar

We're currently set up with an Andersen WDH on a 2022 FC 25 FBT and 2022 F350 diesel TV.

We experienced some very concerning issues on our first trip with the Andersen WDH. We just did ~2000 miles and the Demco coupler unlatched 3 times due to the Andersen WDH. This only happened when the chains were tightened and on rough roads. When the WDH was working and the coupler remained latched, the WDH hitch made a very noticeable difference in trailer control and stability. Unfortunately the unlatching is a serious safety hazard / deal breaker.

The question is, can I put a pin through the Demco to lock it latched? There appears to be a hole that may work for this purpose.

I was taught that standard procedure should be to put a padlock through the coupler to keep it closed a few decades ago. This was to make sure that if you are not with the TV/trailer combo the whole time some jerk might unlatch it as a potentially deadly "joke". Also to visually recheck hitch connection and tires every time returning to combo.

[TNOutback]

The most recent post in this thread is nearly a year old now. I wanted to provide an update from Andersen. I have an Equalizer Hitch right now but due to back issues, I’ve needed to find a lighter solution. The weight of the 2.5”, 9” drop shank, hitch head and 1000# bars totals 106 pounds for the Equalizer! By comparison, the 2.5 inch shank and the Andersen head weighs a little over 30 pounds. Their chain design remains attached to the camper, so that is weight that I’m not having to carry, unlike the Equalizer 1000# bars which weigh a combined 44 pounds.

I’ve spoken with Andersen 3 times over the past 2 months and they have consistently confirmed that their hitch is compatible with the Demco couplers on the 2023 model Airstream trailers. I just placed my order and we will see how this goes . . . .