question about minus sizing snow tires
 

I am getting snow tires for my 2016 Elantra GT. Tirerack's recommended snow tire package suggests 15" wheels. My Elantra GT came with 16" wheels. Minus sizing was recommended as a way of increasing traction in snow. I ordered the tires. Today I got a phone call from Tirerack. They wanted to inform me before shipping the tires that Pennsylvania (the State that I live in) mandates that cars shall not have minus sized tires - and if they do, then they will not pass inspection. What is the logic of this? Is it true? Tire rack says that the minus sized tire package will perform better in the snow, so why does Pennsylvania have this rule? The outside diameter of the tire will be the same for both wheel diameters. I told Tirerack to put a hold on my order until I can look into this. Can someone shed some light on this?

Bull. I live in PA and have minus sized winter tires on 4 cars. Go ahead and order them.

When do you get your car inspected? During the winter? Will the winter tires be on the car when you get it inspected? If not, how will the inspection station know you have minus-sized winter tires. And if you do get it inspected in the winter, swap tires before you go for the inspection. All 4 of my cars get inspected during the spring and summer, well after my winter tires are removed.