3x3 Pole Tongue Extension for a Hymer GT

[OCJohn]

As mentioned in my Dual LPG tank & 6v battery thread, I extended the Hymer's pole tongue by 24" at the same time I started the other mods. I'm guessing this topic will draw some discussion about engineering/safety concerns, so I'm giving it a separate thread to be more searchable for others weighing similar options in the future.

Goals – Improved stability and more room on the tongue. I began thinking about stability on the way home from the dealer in Dallas. Between Fort Stockton and El Paso it got BIG windy. I’m guessing some gusts were 30-45mph. The combination of Texas’ generous speed limits for trucks and tow vehicles, the high winds and a “brand new” trailer I wasn’t yet familiar made for some white-knuckling moments. I slowed to 55mph but even that wasn’t slow enough when being passed by semis doing 70-80(!). Adding room on the tongue started as a secondary goal, evolving from the first.

Options – Tongue extension was about my last thought about how to improve stability. Other solutions considered:

• towing with a full fresh water tank (to add tongue weight and lower center of gravity)
• adding additional tongue weight
• adding a standalone sway control device
• adding a weight distribution hitch (WDH) with sway control
• just suck it up and hope my 7400lb tow vehicle could win any fight with a 2700-3400lb trailer

Filling the fresh water tank helped the one time I tried it. But later reading of another Hymer’s tank falling loose on the freeway, I put that idea aside as something else that needs improvement. I’ve got no experience with standalone sway control devices. I loved the Equal-i-zer hitch I had years ago on a 24-ft enclosed car trailer. But that and similar bar systems were better suited to A-frame tongues, requiring “pole tongue adaptor” hardware and creating interference issues for the trailer jack.

The Andersen hitch stands alone as the only WDH with sway control that doesn’t care if it’s mounted to a pole tongue. It doesn’t need the A-frame geometry or an adaptor to create it. But it would still interfere with the trailer jack. AND it would require removing more chain links than Andersen recommends to be fitted to the Hymer’s short tongue.

So… My primary reason for extending the tongue was to make room to accommodate an Andersen hitch as well as dual batteries/dual LPG tanks and the trailer jack all at once.


Before


After

Making the extension would have been a LOT simpler if there were a standard square tubing size for a telescoping fit inside the existing 3x3 tube. Unfortunately there isn't. It turns out telescoping square tubing sizes are mostly limited to stop sign posts (too light) and trailer hitch receivers (too small). So I cut, sectioned and rewelded my own.






The 1/4x1" copper bar was left over from my battery shunt bus thingie. It's being used for alignment as I weld and to draw heat away and keep me from burning through. (A more experienced welder could surely do without, but I'll take help wherever I can get it.)

After some hammer finish paint, 1/2" grade-8 bolts, longer chains, longer electrical connector and a new coupler (for electric brakes) it turned out like this...

[OCJohn]

Quick conclusion and moral to the story – the extra tongue length and full water tank on our last trip helped stability so much that I'm now reconsidering whether I still want an Andersen hitch.

Also makes me think the good folks (no longer at) Erwin Hymer North America really missed the mark on axle placement/weight distribution.

[gordon2]

Originally Posted by OCJohn

Quick conclusion and moral to the story – the extra tongue length and full water tank on our last trip helped stability so much that I'm now reconsidering whether I still want an Andersen hitch. ...

Maybe that is the quick conclusion and moral of the story for you.. but for me, the quick conclusion and moral to the story is that I should have learned welding.

Nice work.

[Steve Hammel]

Nice job on the tongue. what is the dimension of the new piece you manufactured?

As for the grey water tank falling out I did a real quick effective fix. I went to Harbor Freight and bought some 1" x 12' nylon lashing with the cam style locks. I wove the first piece through the frame triangle cutouts towards the rear and clamped it tight and tied it off before cutting off the excess. I repeated the process towards the front and now the tank is ultra secure. I'll send pics when it gets light out.

[ThomasC]

Nice job. I assume you used a MIG welder. Any trailer I have ever had has gotten that treatment and the Bigfoot I have on order has the cargo box, more for the extra two feet.

[Ken Morton]

My similar experience with our 16' Scamp and Ford F150 has lead me to a similar conclusion. I think the axle is too far forward and with the tanks behind the axle, there is too little tongue weight. I'm guessing that the trailer was originally designed for lower speeds behind smaller tow vehicles. I've weighed the tongue, but when we get it out of storage in the spring, I plan to do some more careful weighing. I photographed our Scamp next to a similar-sized Escape which has the axle placed farther to the rear. Although moving the axle back is not a practical option for the Scamp, I think the comparison does support the idea that the weight distribution could be better. The Scamp has an A-frame tongue, so would require a different method of extension. I'm also pondering moving the spare tire to the tongue and/or moving the tanks forward.

[cpaharley2008]

Re: bolt placement. why not stagger 2 on top on trailer and 2 on bottom on extension? Why all 4 on the top where there will be some forces at the bottom also.

[OCJohn]

Originally Posted by cpaharley2008

Re: bolt placement. why not stagger 2 on top on trailer and 2 on bottom on extension? Why all 4 on the top where there will be some forces at the bottom also.

I just copied bolt placement from the stock coupler. That way if I don’t like it or have any problems with the extension I can just remove it and go back stock.

[Darrell in Al]

I thought about extending the hitch on my Scamp out 2 ft. By welding up a hitch to mount under the factory one, but haven't gotten to it yet. If I start traveling with it more I might need to. Since I'm likely to be getting a new T.V. soon I'll have to put a lift on it too. So many things to think about and do. At least I've got about 10 ft of 2in and 2 1/4 square tube for it waiting for a use.

[Len S]

Have your checked with motor vehicles to see if mods such as yours are valid ?
Just a thought not a criticism.

[OCJohn]

Originally Posted by Len S

Have your checked with motor vehicles to see if mods such as yours are valid ?
Just a thought not a criticism.

Never occurred to me. But I’m more of an ask forgiveness, not permission kinda guy.

[Bruce H]

Thank you John for starting this thread.


I first figured out that a longer trailer tongue improves stability and safety 35 years ago. I had a CJ-7 Jeep and a trailer made out of the back half of a step-side Chevrolet pickup. The tongue was less than three feet long. I purchased a trailer load of wooden posts and started for home. When I reached a speed of 35 mph the trailer began swaying violently and very nearly wrecked me.



I hit upon the solution of welding another four feet onto the tongue. That firmly solved the towing stability problems. I later had another trailer made out of the back half of a Dodge pickup. I welded an eight foot tongue on it at the start. I used it to haul bulk livestock feed. My feed supplier had a giant mixer with electronic scales on it and an augur spout that would dump the feed into a truck or trailer. I came up with "recipe" of the various ingredients I wanted (200lbs of this, 500lbs of that, etc) and they would put it in the mixer and load my trailer. I always got a total of 3,000 lbs. This was the bulk price. The cost to bag it in 50lb bags would have been 50 cents per bag so I saved $30 per load by purchasing bulk. I got a tarp and some rubber tarp straps at the Army Surplus store to cover it with. As an added bonus, when I got home I didn't have to unload it to get it out of the weather. When I got to the farm I parked the trailer across the fence from the cattle feeders and hand fed out of it with buckets, 100lbs per day. I remember lots of January mornings when it was 29 degrees and raining and I would be out there in the dark wading through the mud at 4:30 in the morning putting out feed (which delighted the cattle) before I went to work at my real job.



Enough about my younger days. The bottom line is that with a significantly longer tongue I could pull that heavy trailer safely down the road at 70mph with a half ton pickup and no "equalizer hitch". The extra tongue length is the equalizer. You did a good job on your modification and I would recommend that every trailer owner consider it. And don't be afraid to go even longer.

[Bruce H]

Originally Posted by Len S

Have your checked with motor vehicles to see if mods such as yours are valid ?
Just a thought not a criticism.

Safety should trump bureaucracy. But it doesn't One reason a lot of trailers have such short tongues is that in some jurisdictions trailers are taxed by length, the longer the trailer the greater the tax. Manufacturers make their products more appealing tax wise by chopping another two feet off of the tongue. (thus making the trailer less safe and necessitating dangerous, expensive equalizer hitches and anti-sway devices). Unfortunately this bleeds over into the rest of the country.

[OCJohn]

Originally Posted by Bruce H

One reason a lot of trailers have such short tongues is that in some jurisdictions trailers are taxed by length, the longer the trailer the greater the tax.

I never heard that but it explains a lot.

Back in the 80s I had the unfortunate experience of jackknifing and rolling a 24’ enclosed car trailer, the Suburban TV and the racecar inside. The memory of that instability has never left me and is something I never want to experience again. Dragging the Hymer home to SoCal from Dallas (thru some uncomfortably high winds...) convinced me I needed to do something to improve it’s stability.

[pedalmike]

OCJohn: Thanks for sharing this along with your separate thread on the propane/battery box modifications.

I hauled a 4x8 UHaul box trailer last October for a 2,600 mile trip from Connecticut to Arizona behind my 2009 VW Tiguan. 900 lbs. empty and about 1,600 lbs. with my load in it. The trailer seemed to me to have an extra long tongue, but was incredibly steady and sway-free the entire trip. That UHaul tongue was also a single box section (no A-frame..see photo)

I defer to your race car fabrication background, but I hope the tongue and the extension are up to the demands you will place on it with a loaded trailer. There will be some level of twisting loads on the tongue during times where the trailer is moving over uneven surfaces independently of the tow vehicle. The 2' extension does add more leverage to those twisting forces I think. Getting a second opinion on your mods from a professional experienced in the structural engineering of trailers would be good, but I don't know how you'd go about finding one!

I looked at Hymer's caravan web site for current models they are selling in Europe..most if not all have A-frame tongue configuration. Having said that, most of those trailers have surge type brakes which would increase the stresses on the trailer tongue somewhat.

Mike

[OCJohn]

5-Month UPDATE: this 24" tongue extension has now traveled a couple thousand miles with at least 200 over washboard, dirt roads. Nothing's come loose. There's no sign of fatigue. And the trailer handles MUCH better than before – still without an anti-sway device.

Knowing what I know now (that it works great!) I would probably pass on all the welding/fabrication. The easier plan would be to buy a length of 3x3" square tubing (of the same or heavier wall thickness) that is 2-feet longer than stock and just use the original piece as a drill guide for matching holes.