Ok, maybe not epic. But it could have been. It was a nasty failure none the less. Last week my little Harbor Freight-based mini expedition trailer failed me. Before I get in to the details, a little background.
Those of you who have seen my earlier posts know I drag this little trailer over some pretty rough trails. See post #215
for early pics. And you can see a short video of the type of trails I often traverse in post #335
. (This video happens to be Pearl Pass
After last year's excursions I modified a few things, but that all had to do with the box. The frame held up great (at least as far as I could tell). You can see a video of my design choices and changes in post #638
. At the start of this season, I checked all the fasteners and the general health of the trailer. The bolts on the tongue were just slightly loose, but everything else looked good.
After some mods and improvements, I took it for a short run a few weeks ago (one night out) and all seemed good. In fact I was quite pleased with everything (except the eggs that broke inside my ice chest). I even took it up to Grizzly Lake
(also shown in post #638
) and that trail has a tough obstacle right at the start.
Next it was time to load up for a 4-day trip into the Colorado back country. The group included two people in my TJ, two in a 4-door JK, and one in a 4Runner.
We trekked out towards southwest Colorado and started up our first trail, Hayden Pass
. Suddenly BANG! and the 4Runner radios "hey, I think you're dragging something!"
On this trailer, the tongue is attached in just two places, the front cross member and a middle cross member. The metal failed on the middle cross member causing the bolts to break loose (back end of the tongue). This caused the rear of the tongue to drop and drag on the ground. Fortunately, it was still attached to the the front cross member otherwise the trailer would have broke loose and slammed into the Toyota behind me. We were going up a fairly steep hill and if the tongue breaks loose there is nothing holding the trailer. This failure was dangerous
Why did this happen?
You can see what happened in the pics below. Note that the tongue was fine. Replacing this tongue with a stronger one would not have prevented this.
I believe this failure was due to metal fatigue at the frame. The Harbor Freight trailer -- actually the brand is HAUL-MASTER -- is just not meant for the kind of punishment I subject it to. Also, this design does not use triangular braces on the tongue. Therefore, the tongue acts as a lever
with the pivot point at the front cross member. Each rock I bounced over put tremendous stress on the points where the tongue attaches to the frame, more so at the back. (Imagine driving over a street curb 10 times in a row hitting first with one tire, then the other.) Over time, the metal at the rear joint (and the front joint as well) weakened until it failed, like bending a coat hanger in the same spot repeatedly. I did have more weight in my trailer this trip than previous ones (cooler, water, extra fluids for the Jeep) but I think this failure was brewing for some time.
Probably the easiest thing for me to do is buy another HF trailer and use parts from the old frame to create additional bracing. I think I can use the previous side rails to create triangle braces for the tongue. I could also add another cross brace. The more points the tongue attaches to the better, and the less it can act like a lever. All of my time and effort went into building the box, so I don't want to start over with a different frame.
However, even after it's repaired and improved I don't think I'll ever be able to use it like I had hoped. These little trailers are great on the street and on easy dirt trails, but they are just not suitable for the off-road abuse I've been subjecting mine to. And here's the other thing: even if I built a frame that could withstand anything I could throw at it, the trailer bounces too much to protect and carry things over the trails I had in mind.
That's not a criticism of these HF trailers, or of any expedition trailer. Rather, it's my realization (from lessons learned) that serious trails are not meant for trailers. I need to shift my thinking to using the trailer as a base camp, i.e. something I drop off and come back for after I'm done rock crawling.
Last words and recommendations
I've enjoyed my trailer and will continue to do so. These little trailers are great for pulling behind a Wrangler. They add a lot of space and can go any place a stock Jeep can go. If I were starting again, I would use one of the designs that has triangle bracing for the tongue. In addition to strength, it makes a handy place to attach additional storage.
The pics below show (in this order): rear cross member (view from below); broken piece; broken piece held in place with tape (view from above); front cross member after tongue unbolted (view from below); rear bolt holes in tongue (undamaged); front bolt holes in tongue (undamaged).