Poor Gas Mileage in Winter - Oxidized Fuel???

[jay131866]

I just bought a new 2008 over xmas break and have been driving it about a month now. Originally I got 20-22 MPG on highway, but my last few 5-hr trips I was avg just over 17mpg.

I called Toyota dealer and guy said that all gas places oxidize their fuel in the winter, and to expect worse mileage. I had never heard this before and was wondering if this is true or is he full of BS?

Is ~17 mpg the best I can hope for on the highway? Seems really low since its rated to 20+ on highway. Thanks for your help.

 

[josh220]

I just bought a new 2008 over xmas break and have been driving it about a month now. Originally I got 20-22 MPG on highway, but my last few 5-hr trips I was avg just over 17mpg.

I called Toyota dealer and guy said that all gas places oxidize their fuel in the winter, and to expect worse mileage. I had never heard this before and was wondering if this is true or is he full of BS?

Is ~17 mpg the best I can hope for on the highway? Seems really low since its rated to 20+ on highway. Thanks for your help.

How many miles are on your 4runner so far? And is it a V8 or V6, 2WD or 4WD? You might still be in the break-in period, and your mpg should slowly get higher as time goes on.

I was getting 12mpg city when I first got mine, and I am now getting about 14. I bought it in summer so I think it would be more than a 2mpg increase if it wasn't cold lately.

I get about 18.5 MPG highway, with my V8 4WD so you can use that as a comparison for yours. Also, I get my MPG manually, never by the computer. The computer always reads higher than my actual MPG.

 

[jay131866]

I now have about 3,500 miles on mine, not sure what the official break in period is.

I have a V6 4WD, although I was always in 2WD during the mileage in question. The weird thing is my first trip I got 22 mpg, and then it seemed to drop all the sudden.

Hopefully the computer isn't on the high side or it will be even worse (I took multiple readings from computer).

 

[V8Limited4wd]

yup its the winter gas. im getting around 13mpg city right now and 18mpg hwy. during the summer i usually get 16-22mpg.

 

[josh220]

Next time you fill up, reset one of your trip odometers (there's trip A and trip B). Then drive it normally, and when you fill up the next time, write down how many gallons it took. Divide the mileage you drove by the gallons to get an EXACT reading of how many MPG you got.

The reason the computer is off most of the time is because you can trick it. Hard accelerations will make it drop significantly, but simple things like coasting to red lights will trick it into reading higher.

You should definitely be getting more MPG in a V6 because you are always in 2WD.

 

[seh750]

I called Toyota dealer and guy said that all gas places oxidize their fuel in the winter,

I believe the term is "oxygenated" not "oxidized", but the dealer is correct. There's a different blend of fuel in the winter that supposedly reduces pollution. But it also reduces fuel economy.

I've heard some talk that here in Oregon we're going to be running winter-blend fuel all year.

 

[boston_kevin]

You actually have two factors working against you in the winter...

1) Oxygenated fuel - less efficient, better emissions

2) Colder air - more dense air, harder to push with a higher profile vehicle.

Like others have mentioned, it's totally normal. Just expect the seasonal change.

 

[TechWrench]

Also, now that most places have started switching to ethanol mix gas, which is less energy efficient, we all are suffering a decrease in MPG's.

 

[Jeff Kleb]

Decreased MPG from "oxygenated" fuel is because ethanol has a lower BTU content than straight gasoline. When most stations (here in our area, anyway) use a 10% ethanol blend, it somewhat reduces the "power" contained within each gallon of fuel.

The advantage to ethanol, however, is that it doesn't hurt the octane rating. If you could, in fact, run on straight ethanol - as some dragsters do, your octane rating would probably be well over 100.
:awais:

Some vehicles can run on E85 (85 percent ethanol and 15 percent unleaded gasoline), but their gas mileage suffers almost 20 to 25 percent because of the reduced BTU content; kind of negating any cost savings at the pump.
:cursin:

Diesel fuel has a much, much higher BTU content than gasoline or ethanol, but I suppose that comes with its own set of trouble and difficulties. Modern diesel engines are head and shoulders above those built just ten years ago, so maybe Toyota is eventually going to offer one for the 4Runner in the US market.

I suppose there just ain't no such thing as a free lunch!

 

[josh220]

Even when taking all of that into consideration, you also have to remember that we didn't buy our 4runners for fuel economy. That's what we sacrifice for having a superb vehicle built on a truck frame, and not a car or mini-van frame like other SUV's on the market.