so the story goes......
about a few months after got our new Sierra 366FL it rained, as I looked out the living room window I noticed water filling the window track. it was not draining, I had to put a towel in the track to soak up the water. I called Forest River and discussed Warranty, the first thing he said is none of the outside seals were covered under warranty. so not knowing exactly where the water was coming in from I waited before doing something I might regret. the next time it rained it lasted about 15 minutes and the exact same thing happened. so I am scratching my head trying to figure it out when my neighbor started to explain to me how the drains on his were plugged and how he had to drill them out to fix his problem, wow, I didn't even think of the weep holes. I looked for them only to find they were at the top of the window. then I realized, the manufacture not only installed the window upside down, they also put a left side window on the right side. now that I figured out the real cause of the problem I called Forest River Again. this time My unit was out of factory Warranty. after emailing a dozen pictures and a bit of phone tag, I was informed that they agreed they error with the install at the manufacture. and were willing to fix the issue. after 3 months they tracked down a window manufacture that could produce the same style window I needed to replace. mind you my RV is only 3 years old from date manufactured, 2 years old from date I purchased it. I really give their warranty department a lot of credit for sticking with this from the beginning to the end. problem solved today.
note ; so I found out that Forest River does not keep stock for RV repair, and they also don't use build sheets to get you the correct parts needed. so to get the right part you need you have to find the part number and / or model of the part you need and get it that way.
It is NOT like with a car or truck where the dealer can get you the correct part for your vehicle by using your VIN Number.