Well, crap.

Got home from the Santo Rally and Marc started to change the wheels out so we could put the trailer in the backyard.  This is what he found:

 

Now, I don't know anything about axles and all that stuff, but Marc said something called a leaf spring broke and we were lucky we didn't leave most of the trailer on Highway 6.  Not good.  Marc was able to replace the leaf springs with new ones, so we're good to go!