I drive a 2017 Mercedes GLC 43 AMG. After replacing the original tires (staggered) with new wheels and tires of a different size, I have been unable to get an answer to the question of the correct PSI to inflate them to. Neither Goodyear, Mercedes, TireRack (the retailer) or Firestone (the installer) could provide an answer. The old / new details are below. Any thoughts?
original tires were:
255/40 ZR 21 (FRONT) - 35 PSI recommended 285/35 ZR 21 (REAR) - 38 PSI recommended
I replaced all 4 wheels / tires with 20x9 wheels and
255/45 R 20 GOODYEAR EAGLE SPORT RUNFLAT.
If it helps GAWR is as follows:
2668 FRONT, 2822 REAR.