-10 mpg!
 

Howdy, I wanted to share a recent experience that most people don't think about. This time of year its ugly cold through most of the US. While its like this, most cars MPG suffers for various reasons. Also some of us swap to winter tires to deal with driving in snow and slop. Which also doesn't help.

I've been pretty proud of getting 30% above EPA in my old van in 2015. But this winter I REALLY noticed when all of the above added up to my losing 10 MPG. Or 2 MPG worse than my van's EPA rating.

-10 mpg
 

Welcome to the wonderful world of winter driving!:D

Winter got a late start in NY this year. I finally put my snow tires on less than 12 hours ago and can't wait to take them off! Trying to stay in the top 10. :)

I've seen it happen. Mom's van takes a big hit in winter, even when I started it up and then went after its revs went down when it was a cold start recently the MPGs I got in it were just 18. I can get over 28 when it's already hot on a summer day in near the same trip. And when Mom's driving it, the van can go down to 13 since she idles it to get it warm. And that's after I changed the oil to Full Synthetic Pennzoil Platinum 0w20 - it was getting 10-11 in other years.

Yesterday on a trip where I would expect to use about 5 litres per 100 km in the summer I was actually using over 7. Winter temperatures, winter tyres, snow & ice on the roads, car covered with ice & snow ... it all takes its toll. This car (Merc A series) seems particularly bad for getting ice building up on the rear of the car, on the hatchback. Just the weight alone is significant, plus any effect on air flow.

I loose 10MPG in summer :mad:

With you it is always summer!
Seriously though, why do you lose MPG in summer? Air con? What else?

Slush impacts my mileage, but te biggest factor when roads are clear but it's severely cold seems to be warmup. Even with a block heater, short trips are awful in winter for me. Doing the same 15 mile trip, I might get 50mpg the first time, 65mpg on the way back, 75mpg on the way there the second time, and 80mpg on the second return trip. Despite coolant temperatures peaking after ~2-5 miles, mpg continues to climb for another 40+ miles.

Snow helps me because traffic on the highway is slower.

The other factor that has a negative impact on winter mileage is the "winter" gas...which up in Canada they advertise as a good thing.
What they don't tell you is it reduces MPG's (increases L/100km)

Copied from one of the gas-station websites:

"...
It provides extra protection by helping with cold weather starts and helping to prevent fuel line freezing, at no extra cost.
WinterGas is available from November through March in all gasoline grades at Petro-Canada gas stations across Canada.
..."