2013 Chevy Express 3500 Passenger Van - Suspension Upgrade

I'm looking into the Bilstein 4600's, both front and rear. It looks like the only thing Bilstein makes that will fit my vehicle.

My tires are Bridgestone V-Steel R1B 265's, Load range is E and the max pressure is 90 psi on the tire. The door panel lists my pressures should be set at 50psi in the front and 80psi in the rear. I checked the owners manual and I don't see any recommendation to lower those pressures. Wouldn't lower than stated pressures cause tire overheating and risk damage to the sidewalls?