I'll start by saying your best bet to do a tire chalk test. There's a couple good Youtube videos if you don't know how.
Ok, here's some
approximate numbers. According to page 3 of the
2017_ram_2500_towing_chart you truck's base weight is 4000lbs. in the front and 3000lbs in the rear.
Firestone doesn't publish a Load Inflation Table so we'll use the one from
Toyo to get close. Your size is on page 24 ... LT285/60R20 ####=load capacity per tire, (XX)=psi - 2020(35) 2220(40)
2410(
45) 2600(50) 2775(55)
2950(
60) 3085(65) 3285(70) 3445(75) 3640(80).
So at the recommended
60psi for the fronts your tires have the capacity to carry
2950 x 2 = 5900lbs but the front of your truck only weighs 4000lbs. Even at a 20% margin of error a psi of
45 = 4810lbs (
2410x2). Simply apply the same math for the rears.
IF it was my truck I'd run 50 front & 40 rear. In fact, that's what I run with my Cooper A/T3's with great results.
And IF you don't like the annoying lights and warnings, I can help take care of that. Shoot me a PM for details.