Not to hijack the hijack, but that SUCKS.
I didn't have a rig on the trailer, just a pair of axles when something similar happened to me.
I went down to Lindon to pick up some 60s that I bought from the for sale section here. Borrowed trailer, moving at the time... etc.
On the way back, cruising on the freeway... I cross an expansion joint, and I hear this weird "SPRONG" type noise.
Check mirrors... nothing dragging or flying off, ratchet straps still in the right places, trailer tracking well... hmmm... that was weird.
Seconds later, POP! WTF???
I check mirrors. Driver side first, since I was in the right lane, the driver side could have caused more expensive issues... nothing wrong. Check Pass side mirror just in time to WATCH the second tire blow.
I pull over, start jacking up.
UHP shows up, and has a floor jack, which worked much better (I mentioned I was moving, which emptied the tow rig of the floorjack, and hi lift jack, and damn near everything else that I would have normally had at my disposal.
We took both blowns off, and got the spare off the trailer... well guess what. Wrong lug pattern.
I caled my dad, and he headed down with another spare that was supposed to fit, and some other tools and stuff.
While waiting for my dad I figured out what the sprong noise was. the inner fender had popped past it's booger welds and had eaten the indide of the tires. I checked and made sure that axles weren't pushing on the inner fenders, and they werent. So just crap luck in my case.
Dad shows up with the spare, and its wrong too. I pulled the rig further off the road, and pulled the tire off the NON brake axle on the good side, put it on the brake axle on the bad side.
Then we decided to address the fenders. We had some nails, a hammer, and some screws. We worked at it and made some holes in the inner skirts with the nails, and then screwed the skirts to the wood planking of the trailer. We limped home on frontage roads, and thru neighborhoods, but got home none the less.
Adventures like this are always fun. On the upside, my dad won a McGyver award that night for figuring out how to keep the skirts off the tires.