Tires: Tire Pressure, 20 inch tires, 2007 gmc sierra

Question
I have recently upgraded my 2007 GMC Sierra CrewCab from factory 17inch wheel/tires to opt 20inch 275/55/20 inch tires and wheels. Factory 17inch were inflated to 35psi. The Bridgestone Alenza H/L 20inch call for 30Psi. The Bridgestone retailer inflated them to 30 psi. Just wanted to check to see if this is the same setting on pressure as the Factory  would set the pressure. Did not want to ruin a set of new tires. I want to get the best fuel economy and longest life out of these tires. thks.

Answer
Ken,

GM did supply these types of vehicle with that size and the vehicle tire placards said to use 30 psi.

However, these tires are also lower in load carrying capacity than other tires where GM recommended 35 psi - and I would think that if fuel economy and tire wear are your goals, then 35 psi will be better.