How much do I offer for a brand new 2017 Ram 2500 Diesel?

I believe $10k including incentives is the norm for Ram trucks. look on cars.com for ram long horns in the $70k price range. see what dealers advertise the sales price for; that will give you a starting point.

buy a new truck shouldn't be a hateful experience, know what you want to pay and don't waste time with dealerships that won't negotiate. know what you want, options etc. then know what incentives are out there and go to the dealership with your ammo. you're in the driver's seat not them.