First its story time….questions will be asked later
I have had my 2005 lund Fisherman since brand new. I put it on a custom fit bunk trailer with Goodyear Marathon tires.
This last weekend as my Dad and I headed out the door to drive up to Devil’s Lake for some much needed relaxation I gave him the tire gauge. Both trailer tires checked out at 60 psi. The pressure recommended on the tire. I have never had any issues with either tire wearing goofy, leaking or anything! 80 miles down the road the passenger side tire blows 
we change the tire and put the spare on. call Goodyear in St. Cloud and get a new Goodyear marathon tire put on hold to replace the blown one.
Stop at goodyear get the new spare and put the brand new tire on the spare holder.
Go to Devil’s lake, fish have fun relax and head home today. As we get to maple grove I look in the Drivers side mirror and now the other tire is flat! 
Luckily I pulled over quick enough so that didn’t disintegrate. changed that and luckily we bought that new spare because we needed it. go to drive away and wouldn’t you know it? I picked up a carriage bolt in my pick-up tire
Now I’m pissed!!! We change the tire and of course the spare is low and just in time the highway helper pulls up. probably got the call when my trailer tire went and found us when the pick-up tire went. he gave us some air and we are on our way. as we’re driving we wonder….How much does that boat and trailer weigh and why did the cords seperate on those tires?
We stop and weigh the whole works at a truck scale and the trailer weighs 3260 pounds. its rated for 3750 the tires have an individual rating of 1870.
How long have your tires lasted on your trailers and has anyone seen the same thing after 3-4 years and being stored inside?
meanwhile I’m off to buy new tires