Snow Tires
 

I'm not in an area that gets a lot of snow therefore I run all season tires year round and just drive a little slower and more cautious when we do have bad winter weather conditions. I know snow tires usually have a deeper tread. softer rubber compound and more aggressive tread pattern. All this makes me wonder how much others are being penalized on mileage during the winter when there's no snow on the ground and they're running snow tires. How much decrease in mileage does everyone contribute to their usage of snow tires?

I don't see a lot of difference. Maybe the the snow tires cost a bit of MPG but then on average I guess I am driving a bit slower which may gain a little MPG. Overall it all seems to cancel out.

I run snow tires year around (Nokian Hakkapeliitta). Those tires are snow rated, plus they claim low rolling resistance. I am currently running about 40 PSI in the tires.

I do know that my truck coasts better than my wife's Ford Focus, a friends GM Tahoe, and a government Chevrolet Colorado. I did one informal, not documented, test of tire pressure. It coasted noticeably better at 45 PSI than at 32 PSI, so I pumped up the tires and never looked back.

I figured running the softer compound snow tires year round would wear them out pretty fast on dry hot pavement. I remember as a child my dad ran bias ply snow tires during the winter and when spring came he'd take them off and store them till the next winter. When they came out with all season radials I remember dad talking about how much better they were than the bias ply snow tires he'd been using in years past. I've been driving 43 years and some change. I've never used snow tires and can't remember ever being in a position where I absolutely needed them over the all seasons. I'll admit the snow tires would have probably got better traction but I've driven on all seasons in snow up to about 15-16" deep and on ice in several ice storms. I used to live in the Piedmont of NC, we didn't get a lot of snow there but we had a few pretty good ice storms in the 25 years I lived there. Now I live in south central KY, we don't usually get more than 5 small to average snow falls per winter and just like NC we get the occasional ice storm. Thus far this winter we've only had one dusting of snow and the ground was so wet then it lasted only as long as it was snowing.

I've read that some of the fuel economy world records have been set on snow tires, because some of the same compounds that keep the tires soft when it gets cold, also decrease rolling resistance.

Whether that's true I can't say for certain, but I typically don't see much, if any drop from the tires themselves, just from the weather getting cold.

I haven't seen any difference in fuel economy between summer tires and snow tires. I do run a narrower tire in the winter.

The stock tires on my VW are 225/45R-17 while the Micheline X-Ice snow tires are 205/55R-16. Wheel weight is the same as the snows are on steel wheels.

I didn't see a change on the Prius either.

My almost new Uniroyal MS Plus 77 winter tires (175/65R15 on steel rims) are slightly less economical than my old set of Continental WinterContact TS 810 S (same size/rim).
They do have considerably more grip in the rain though also corner better in the dry and make a more pleasant sound at speed, even if they aren't really quieter.

The Contis beat my summer tires on economy in similar conditions. The Uniroyals not so much.

The Contis lasted for about 80,000 km and still have enough thread (well above minimum) to serve as rears / emergency spares. Had I known how soft this winter would be then I'd not have replaced them yet.
But I knew from last winter that their grip in snow was getting worse, and I want my tires to work well in the worst conditions they are likely to meet, not just the best.