ok lol I was thinking something was wrong with my calculator....I know if I get out on a long run, like when I headed out west or even a 3 hour run to Virginia I was getting close to 18 but my normal driving around home in the summer is closer to 17. I was just venting since I really just noticed the gauge dropping quicker lol....

 

If I went to some 18's instead of my stock 20's would it help my mileage. It might be a stupid question but myself I dont like 20in wheels in the first place.

 

Tire diameter, getting a smaller tire diameter, is really the only thing that matters. 18's would (likely) weigh a little less, so with the same exact size tire on each, the 18's could weigh a touch less, but this would yield a negligible difference in fuel mileage. It's all about total tire diameter.

 

Thought so wanted to get someone else opinion.
Thanks.

 

Quite a bit of the information posted here is in disagreement with what I have read. The winter blend is not nearly as likely the cause as that "few minutes" of warm up. Quit warming up and see what happens.

 

So far I have been getting about the same with Shell 87 octane fuel. I drive all highway and I don't go over 70mph. I've got stock 20s and I always use the block heater too so I don't have to let it idle as long to warm up the engine. 18.1 mpg no lie!

 

The winter blend 100% causes a decrease in mpg...

 

I agree with the no warm up, I still average 31mpg with my car, 1mpg less than what I see in summer commutes. I layer up, get out and go. About the only times I idle to warm up is whenthe windshield is a sheet of ice.

 

Absolutely!

 

Absolutely! the winter blend causes a decrease--not as much as warming up or just the fact that it is cold outside and the vehicle runs richer.

I read the popular mechanics article. I didn't see where they said the winter blend lowers gas mileage. I did learn that there are as many as 20 different blends of fuel. The article didn't go very deep into that:

POPULAR MECHANICS EXCERPT

The price of gas is a confusing, convoluted issue. But before we get into that, what exactly is the difference between summer and winter gas, anyway? Basically, winter gas is cheaper but not as pure, and worse for the environment.

The nation has some 20 different blends of gasoline to meet overlapping state and federal guidelines. The reason for the different grades of gas comes down to trying to control VOCs (volatile organic compounds) that are more likely to evaporate the hotter it gets. More VOCs equal more smog, especially in summer, when the heat in the atmosphere increases the propensity for atmospheric ozone and adding in the VOCs increases the intensity of the smog.

I have not found one article verifying that winter gas significantly lowers gas mileage. the excerpt below is typical--not chosen to make the point:

SOME OTHER OPINION THAT IS REPEATED MANY TIMES:

Apart from the pricing issue, winter-grade gasoline does yield slightly less energy than the summer blend, Mark, but only by about 1.7 percent on average, according to the EPA. Ethanol's impact is far greater, dropping energy content — and fuel mileage — by more like 30 percent. Still, winter-blend gas imposes its minimal loss on every gallon your engine burns, whereas E10 is a blend of 90 percent gasoline and only 10 percent ethanol, which mitigates ethanol's mileage-lowering quality.

Another reason it's difficult to determine the degree to which seasonal gas formulations affect mileage is that other factors come to play, and with greater impact. An ice-cold engine needs a "richer" gas-air mixture to fire up and idle, and until the engine reaches operating temperature, you're burning more gas compared with startups in the lazy, hazy days of summer. Factors other than winter-blend gas can cut far deeper into mileage — by 20 percent or more — according to the EPA. These include excessive idling (no need to "warm up the engine" in cars made in the last decade or so) and poor road conditions, as well as non-seasonal issues such as lead-foot acceleration, traffic congestion, engine efficiency (need a tuneup?), tire pressure, head winds and hills.

At the end of the road, it's unlikely that winter-blend gas by itself is crimping your mileage in a significant way. You might be able to boost your cold-weather mileage by addressing some of the other matters, or maybe you should try yet another mechanic. Those you've talked to about the problem don't seem up to speed with their fuel facts.

Please forward any information to the contrary and remember we have been told that there are 70 blends and a great deal of information that can not be verified. Remember our "common sense" approach brought us mythbusters. What makes sense or is common knowledge doesn't always turn out to be true. I might even ask mythbusters to investigate.

 

I think it would very interesting to see Mythbusters do this. They tested tailgate up vs. tailgate down mpg, IIRC.

At the end of the day, people get worse mileage in the winter, no matter what it's attributed to!

 

I read the links. They explained the difference and the energy drop is minor. The cold weather has a bigger impact. If you really think you can drive like a maniac or grandma and get the same mileage, you two might agree, but you can agree on being incorrect. Driving style matters.

 

I agree. Let's all email mythbusters on this one. I think they should do one is cool weather--like 50 and another where it is like 20 or less. and see the results.

They also dis one where they were hyper-mileing--shutting the key off instead of idling, 45 on the hwy...almost double their mileage. Hyper milers got 31 in an f150.

 

Only 20*? That's still Fall weather. They need to test winter temps, below 0, closer to -20*

 

suggest it to mythbusters