Luvnlife

http://www.gmc.com/gmc-life/trucks/sierra-denali-all-mountain-concept

Thanks members.

I’ve read here about bigger tires causing loss of fuel mileage. I need the physics explained to me. If I replace my stock 275/55R20s with 285/65R20s I will be going from a 31.9” tire to a 34.5” diameter tire. I understand the wider heavier tire but, in effect with the larger tire I am probably reducing my final drive ratio from 3.43 - to what, 3.08. At that ratio my engine is not turning as high RPM for the same speed. Less RPM less fuel?

Update, dealer will replace all wheels and center caps under warranty. Upgraded to the same wheel in chrome.

How does the difference in tire diameter effect speedometer and any other system?

Thanks guys, truck was purchased as a certified used vehicle. Still has some original warranty plus addition 2 years. What I was looking for was similar problems with other vehicles. Always planned to go back to dealer.

2015 GMC Sierra SLT 20” wheels. Coating appears to be coming off wheel spokes and center cap. Anyone else seeing this. This is a Florida truck.

http://www.ebay.com/itm/2014-15-GMC-Sierra-1500-CHROME-Snap-On-Grille-Overlay-3-Bar-Grill-Covers-Inserts-/381850984277 Inserts for SLE or SLT to give 2017 Denali look. Frank