I noticed today after a hard rain that there was a small amount of water leaking into the interior of my mustang at the passenger side C pillar between the seams of the plastic panels. The water streamed down the interior plastic panels and ended up dampening the fabric portion of the passenger side rear seat bottom (between the plastic panel and the seat).
Has anyone heard of this issue happening before and know of any possible causes? My only guess is that water is leaking under the rear window due to a bad seal while setting in the rear window.
The car is only 9 months old and this is the first time I noticed the leak (so it may have been leaking the whole time.)
Honestly on such new cars I am not sure why people worry themselves with the problems. This is what the BUMPER TO BUMPER Warranty is for. This is the dealerships problem to diagnose and fix at their expense.
With that said I think you assumption is correct, but take to the dealer and let them do the work for no cost to you.
(11.)2012 GT500 silver with red stripe, SVT performance package, and Recaro seats.
2018 Honda Civic Type R
Past Mustangs in order and color of text.
(1.)2000, (2.)2004, (3.)2006GT/Auto traded for (4.)2006GT/Manual, (5.)1996, (6.)2011GT, (7.)2003GT, (8.)2006GT, (9)2013 Boss 302, and (10.) 2002GT
(I have owned a few non Mustang cars over the years as well, but always try to have a Mustang with it or come quickly back to a Mustang!)