eatSleepWoof's 2019 Erwin Hymer Touring GT550 (1 Viewer)

[e9999]

yes, that is what I envisioned. Rather odd design. And if that is a torsion axle, the axle could well serve as the only cross-member itself. But that tongue is a very long cantilevered unit. (Which could contribute to swaying too, maybe?) Probably why it's fairly large in cross section. And, really, with the original design if the tongue were to bend a bit it would not hurt much, except possibly if there is an unforgiving anchor point between body and tongue in the front. But the situation becomes fundamentally different if you attach the body to those front arms via the jack points. Now if the tongue bends, even within the elastic range and recovers, you are putting stress on the new body attachments. And this may be exacerbated because the attachment point of your side arms is far forward of the axle, so more leverage wrt the axle.
But you are probably right that that won't hurt anything and the tongue may not bend significantly, in which case you are fine. Or if there is play in the jack point mounts, that might be fine too.
I'm probably overanalyzing this, but am bringing this up because damaging the integrity of a fiberglass shell like this seems problematic. And the designers probably thought this thing over very carefully. Personally, I would not be too keen on modifying their design without checking all this very carefully. And if I were to plan on doing some offroading with this trailer, I would make very sure that the attachments between tub and frame will be able to withstand it. There may be a lot of flexing and stresses going on that was probably not anticipated for an asphalt-designed unit, and I don't think fiberglass shells are very forgiving.
But you are doing nice work, it's nice to learn from it, I hope you keep on telling us what you are doing and finding out.

 

[80t0ylc]

I've been reading through today's posts and had a couple of thoughts. If both front and rear stabillizers - you really can't call them jacks - are original equipment (installed by the manufacturer), they must be attached to some sort of internal frame. And as you know, are meant to suport the trailer and keep the trailer stable while camping. I would verify that with the manufacturer, first. And also, as @e9999 has suggested, get their opinion with both your mods, but also how much you can rely on the stabilizer mount's structural strength. You may find out that they're more sound than the C channels. Just a thought.

 

[eatSleepWoof]

I've been reading through today's posts and had a couple of thoughts. If both front and rear stabillizers - you really can't call them jacks - are original equipment (installed by the manufacturer), they must be attached to some sort of internal frame. And as you know, are meant to suport the trailer and keep the trailer stable while camping. I would verify that with the manufacturer, first. And also, as @e9999 has suggested, get their opinion with both your mods, but also how much you can rely on the stabilizer mount's structural strength. You may find out that they're more sound than the C channels. Just a thought.

Unfortunately there's no manufacturer to contact - they went out of business after shady financial dealings.

I'm fairly sure there's no internal frame at those stabilizer points. I'll confirm this when it comes time to remove the new additions and get them powdercoated, as I'll have to remove the bolts that go through the fibreglass/metal sandwich; it'll be evident then.

 

[e9999]

Yes, I think it is unlikely there is an internal frame at the stabilizers points, but I would hope for a metal plate embedded in the fiberglass. Does not eliminate the possibly of the glass cracking but at least spreads the forces over a larger area, so lower stress. I would hope that there may be something more serious where the tub attaches to the tongue/frame/axle, though.

 

[eatSleepWoof]

Yes, I think it is unlikely there is an internal frame at the stabilizers points, but I would hope for a metal plate embedded in the fiberglass. Does not eliminate the possibly of the glass cracking but at least spreads the forces over a larger area, so lower stress. I would hope that there may be something more serious where the tub attaches to the tongue/frame/axle, though.

Folks on a Facebook group for these forums have mentioned an internal, aluminium frame in the front of the trailer. I'm hopeful that's the case, but am not betting on it.

It's worth noting that in all points where metal connects to the fibreglass body, between the two is a piece of thick rubber-like material. Perhaps that's intended to flex instead of the fibreglass.

 

[e9999]

yes, they may have used an internal frame for the main body, perhaps to be able to keep the fiberglass reasonably thin. And, indeed, on the front sides, if you are walking and standing there, there is no direct support from the metal frame under the fiberglass from what you drew. So it would make sense to have some sort of subframe to reinforce those corners. And then it would also make sense in turn to connect the stabilizers to that subframe if there is one. That would be good for your plans. You could try with a magnet if you can't directly see anything, but of course they could have used Aluminum to save weight. How thick is that fiberglass shell, you think?

And, yes, you definitely want some flex and vibration absorption. Like on our trucks.

 

[eatSleepWoof]

Went to the shop today to pick up the trailer only to discover it sitting sky high! Instead of the 5" lift I wanted, it was lifted 9.5"! Have to say it looked awesome, but at that point it wouldn't fit into my garage.

Turns out the shop ordered a height-adjustable torsion axle. Dexter calls these TorFlex, I believe. By removing the wheel and hub, you can re-set the hub on a 100-degree spindle, in a different position, to change the angle of the torsion arms. This, in turn, results in raising or lowering the trailer. Pretty cool.

I've asked the shop to set it to the desired 5" lift, and will pick it up tomorrow. They also boxed in the original (notched) c-channel frame, and threw on a coat of paint over it. The paint will undoubtably come off with time (not a big deal, I'll fix that), but overall it looks fantastic.

Will take photos of the lift once it's home tomorrow.

Also asked them to remove all new frame additions to make it easier for me to take everything to powdercoating tomorrow. Aiming to have everything assembled in final form sometime next week.

 

[eatSleepWoof]

Trailer is now lifted!

The lowest point is the grey water dump valve, which previously sat at 4 1/2" of clearance; there is now 9 3/4" under the same valve, and the trailer still easily fits into my 8' garage door.

All of the custom metal parts are at the powdercoater, and I hope to have them back early next week.

 

[e9999]

nice. Would it be possible to lift that valve a bit?

 

[eatSleepWoof]

nice. Would it be possible to lift that valve a bit?

Not really. I looked at it, but at best I’d gain a 1/4” or so. To get significant gains I’d have to remove the grey and fresh water tanks, plus AC and a bunch of wiring. That’s too much effort. Don’t really need more than what I’ve got now, either.

 

[eatSleepWoof]

Here is a photo dump showing how the lift was done.

 

[e9999]

interesting. Looks pretty beefy. The adjustable suspension arms are great to have. Nicely done!
It does look like you could have had the body an inch or two closer to the axle, though, with smaller vertical blocks. Is there a reason you didn't do that?
Is that valve we see the one you mentioned above? It does look quite a bit higher than the axle bottom.

I have a torsion axle someplace, I may just cut it open one of these days to see how it is inside...

 

[80t0ylc]

Looks better aligned height - wise for your hitch & tow rig. When you get your powdercoated parts back, installed and your tongue weight ratio balanced, I'll bet it'll tow fine. Now with the elec brakes setup it shouldn't be a burden to stop. Looks to be coming along fine

 

[eatSleepWoof]

interesting. Looks pretty beefy. The adjustable suspension arms are great to have. Nicely done!
It does look like you could have had the body an inch or two closer to the axle, though, with smaller vertical blocks. Is there a reason you didn't do that?
Is that valve we see the one you mentioned above? It does look quite a bit higher than the axle bottom.

I have a torsion axle someplace, I may just cut it open one of these days to see how it is inside...

That was a design choice made by the axle shop. I agree it would have been nicer to have the axle a bit higher, but I suspect they wanted to leave enough room to be able to drop the grey water tank (which is overtop of the axle) with ease. You can kind of see the valve in image #4, on the far (driver's) side of the trailer, behind the wheel.

Looks better aligned height - wise for your hitch & tow rig. When you get your powdercoated parts back, installed and your tongue weight ratio balanced, I'll bet it'll tow fine. Now with the elec brakes setup it shouldn't be a burden to stop. Looks to be coming along fine

Yes, expecting it to be a much better towing experience. Looking forward to taking it out for ~5 days starting next weekend!

 

[e9999]

good point about the tank, it does look like the axle is fully welded in and can't be taken off short of cutting, but that should not be too difficult if ever needed, and easy to put back on (although I would use some bolts at that point).

What's the clearance under the axle?

One good thing with this kind of suspension is that it would not take very long to lift it a lot more just before an offroad trip. (Just don't forget about it when you come back to the garage... )

 

[eatSleepWoof]

I haven't measured it, but I'd guesstimate around 5" under the axle itself. Not a lot, but not really an issue, either.

---

Last week I got the parts back from powdercoating and installed some of them.


Tongue is done, storage platform is mounted, propane converted to dual tanks with an automatic changeover regulator, battery is back in place, tie-down options on platform done.

There is room for a total of 8 (!!) 20L jerry cans; this means I can take 80L of fuel (to match the 80L gas tank in my vehicle) and another 80L of water, all on the tongue.

Electric brakes were also wired.

 

[80t0ylc]

That storage platform is impressive! Just a quick calculation that 80L of water + 80L of fuel is going to be about 300 lbs or 136 KG. If that is fitting in with your plans for tongue balancing, remember that's going to vary as it's used. I had that problem before, so just something to think about.

 

[eatSleepWoof]

That storage platform is impressive! Just a quick calculation that 80L of water + 80L of fuel is going to be about 300 or 136 KG. If that is fitting in with your plans for tongue balancing, remember that's going to vary as it's used. I had that problem before, so just something to think about.

At this point, I'm of the opinion that the more weight there is on the tongue, the better. The trailer handled very well this past weekend (with 40L of gas and 40L of water, plus battery and two, 20lb propane tanks), but it would be even more stable with additional tongue weight. At least, I don't see how an extra 40L would make anything worse.

Realistically, I don't be carrying 160L of liquid very often. I might do it when we do my (dream) trip of visiting the Dempster Hwy in Yukon, as gas stations will be very sparse there, and I will need a ton of fuel. I'll probably bring 100-120L of fuel, and an extra 40L of water (to supplement the ~80L in the fresh water tank). That will be a very rare setup. 99% of the time, it'll be no more than 80L up front. Then again, I always have the option of putting extra jerry cans in the LX, too. Flexibility is good .

 

[eatSleepWoof]

This was the maiden trip this past weekend. Three days, two nights.

We went camping in autumn, and came back in the dead of winter. 40km driving on fresh snow (about 20cm deep) on the way home - great fun.

 

[ukrboy]

Love the winter shots!