I broke my old trailer because I let the shocks wear out and I
drove faster than the bouncy trailer could handle. But that has
made me sensitive to wanting a lower center of gravity in my
The Chaser has a Engel 45 fridge/freezer that runs off of an
AGM house battery. For the rebuild I wanted to increase the
battery size and move it from the tool box (which I access
several times a day on the trail) to inside the trailer under the bed.
A BattleBot friend suggested putting the batteries between the
trailing arms, and I decided to go all the way with his idea.
As a rancher I have all sorts of cut-off metal pieces, so I started
with a piece of 8x8 0.250 inch steel tubing. I cut the top off and
cut it to the length of two AGM batteries.
I welded on some pieces of 2x3" angle to make the sides and a
couple of pieces of plate to the front and back.
I added a 2x2 inch tubing to the frame and sandwiched the box
between the two horizontal members.
Before welding the box in place, I drilled several 1/4 inch holes
in the side angles and welded some nuts on the bottom to make
one person assembly easier.
And for added insurance against a rogue rock, I added a 1/4 inch
skid plate to the front of the battery box, supported by a footlong
piece of 1.5 inch tubing running between the horizontal frame
member and the bottom of the battery box (seen here with
the trailer upside-down):
Here's the frame with the batteries inside:
The front of the box sticks about 2 inches lower than the trailing
arms, but is still has 18 inches of clearance. Any rock that would
hit the box would have already taken out the Jeep rear diff. The
bottom of the battery box is also higher than the middle of the tires.
My latest task was to cut a rectangular hole in the aluminum floor
plate to allow access to the batteries from under the bed:
The end result is that I moved 130 pounds lower by at least one
foot, which should help with the center of gravity.
Of course the proof will be in the pudding after I haul it around
some trails to see whether the trailer behaves well.