Rear window not sealed?

Hey guys, wondering if anyone else has this issue? I rarely leave my rear window open but have tried to take pictures to show the dust/dirt buildup all around the interior of the window inside the cab... Probably being way to picky but just making sure that no water is getting inside the cab if dust builds up this quick, truck is under 10k miles. Thanks!

Sorry for low light pics, tried to get as much contrast as poss. to show dirt

 

Clean it out thoroughly, close & latch the window, don't touch it for a few months and see if dust/water re-appears. If it does, take it to dealer.

 

Will do...didnt even think of the dealer option haha, not used to having a warranty!

 

After you've thoroughly cleaned and dried it, you can cram some paper towels in the suspect spots. If water gets in, it'll affect the texture of the paper towel and you'll be able to spot it quite easily (otherwise the water could evaporate and not leave much signs of having been there).