Well,I am gonna finally add my expierence to this thread as well,it's true I expected the bed to weigh about 12,200 to 12,400 lbs,and that would have been well within the rated load capacity of this particular trailer,which I purchased new in June of 2011 from Kaufman.
It is not a typical 14,000 lb GVW deckover,but a 17,000 lb GVW, this is based on transferring 3000 lbs to the towing vehicle itself,evidently the tires themselves are the weak link on this particular style of trailer.
The tires were 235/80R16 load range E trailer tires that have a 3520 lb maximum load rating at 80 psi cold,I did have all tires at the maximum cold pressure.
I have a correctly installed 30,000 lb rated hitch in my dually rated for a 10,000 lb vertical load,I definetly do my best to go above and beyond with my towing equipment.
The dually had about 158,000 miles on it when I decided to install a Edge EZ module,which increases the HP output by boosting the rail pressure to the injectors,evidently it surpassed the sealing capability of the injector O rings and started leaking fuel into the oil.
So,after it's all said and done,It's getting 6 new injectors @ $384 ea,plus a $1200 core charge,$3504 total.
I removed the power module as soon as I got home,no further problems.
Granted,yes we probably should have weighed it beforehand,and verified the exact weight of the wrecker bed.
I honestly do not believe the trailer or truck were beyond their carrying capacity,I believe the trailer tires themselves were at fault.