A Load Range D may in fact work well, Until the day you have a tragic accident. If prosecution attorney can in any way point to a tire issue and you have D instead of E's as Dodge instructs to use, your a goner. Expert witness will bring out things about tires you never even heard about. He will easily point out why Load Range E were installed by Dodge when the truck was built. To save a few bucks now on tires, compared to financial destruction in court, go for it.
This is the Day and Age of SUE
Paul
Have to jump in my 2cents worth, he is right. I've gone to tire "training" on this issue in the business I'm in and yes it would be brought up in court. Sidewall stiffness is an issue between "D" and "E". I personally had a blowout on the rear of my truck with "D" rated tires on a one ton Ford that called for "E", could it have been a factor, no one knows but changing a tire on the side of the interstate with camper hooked up shaking violently with every passing big rig I went back to the "E" rated tires.