One of the things I wished for in my 2005 3670 was heat in the bathroom! I was happy to see the heat duct in our 2010 3605 until we ran the furnace, it sounded like a jet engine in there. Our last trip of the season was spent in nights in the low 30s so I decided something had to be done. Here is a link to how I re-routed the duct and eliminated the noise.
http://photobucket.com/Furnace_mods
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Mike & Donna Ishler Ontario, NY KE2LU FN13
2017 3720RL TST S637's
2017 Dodge 3500 Laramie CTD 4x4 Auto
