What's this 5 yr crap?
If it leaks, does it mean it wasn't built properly from day one? If so, and you were the original purchaser, you have a case for a day in court.
Unless,:
Did it wear out for wear and tear?
Is it a replacement maintenance item?
Was it abused?
Was it used commercially?
Is it called for recaulking per owners manual?
You just need an expert to show at small claims court with some photosin hand - may have to travel and take time.
But this usually doesn't occur when people have to pay experts and lawyers, it's not worth it, and manufactuers know there is no legal defintion of "quality" for plaintiffs to bring to court.
No other recourse, so hang lemons from it and park it in front of local Grady dealer / town boat ramp / town marina dock, etc,. and blog all day on THT. This technique has been well established due to car manufactures screw ups, same story.