RSN in 2008 Dodge Sprinter

2008 HiRoof/170”
I've started to notice RSN with 125k on the odometer. By the advice of this forum (Doktor A especially) I change tranny fluid (all 8 qtrs.).
It help.... a little.
10k miles later it was very bad: loud and vibrant, basically at 25, 45 and 65 mph.
I change tires (?!!): it helped, but still, I can feel/hear RSN. Its especially annoying at cruising speeds 65 – 70mph when RSN is on and off all the time.....
Any advice?

We are beginning to see this issue and are working with a new torque converter design. Private message me, maybe we can help.

Thank you, John
Sprinter Store
http://sprinterstore.com/
A division of Upscale Automotive, Inc.
19460 SW 89th Ave.
Tualatin, OR 97062
503-692-0846