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Discussion Starter #1
Last weekend I put my 15" winter wheels/tires on and wow! I've gone from averaging 35 mpg's to 39 mpg's over the past 2000 miles. Yes I know the smaller wheels and tires have a smaller diameter and aren't really taking me as far as my stock 17's and have calculated the distance I'm going is 3.4% less now. I've taken this into account and adjusted my ultragauge appropriately to get 39mpg. My winter tires are on steel wheels.
 

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Last weekend I put my 15" winter wheels/tires on and wow! I've gone from averaging 35 mpg's to 39 mpg's over the past 2000 miles. Yes I know the smaller wheels and tires have a smaller diameter and aren't really taking me as far as my stock 17's and have calculated the distance I'm going is 3.4% less now. I've taken this into account and adjusted my ultragauge appropriately to get 39mpg. My winter tires are on steel wheels.
How often did you check your air pressure on your previous tires? Low pressure, even just 2-3psi, can make a HUGE difference in mpg.
 

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Monthly. I was running 35 psi. My 17" tires are also lrr tires. I ran this same setup last winter and didn't notice much of an mpg difference but my winter wheels are on early this year and currently my mpgs aren't affected by long engine warm ups and below zero temps yet. Over the last 2000 miles I've driven this week my dash mpg shows 41.2 mpg
 

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Monthly. I was running 35 psi. My 17" tires are also lrr tires. I ran this same setup last winter and didn't notice much of an mpg difference but my winter wheels are on early this year and currently my mpgs aren't affected by long engine warm ups and below zero temps yet. Over the last 2000 miles I've driven this week my dash mpg shows 41.2 mpg
What tires did you go with? I'm still debating going from my 215/50-17's to the new Blizzak's in either 205/55-16, or 195/60-16. The former being slightly larger diameter, the latter, slightly smaller diameter than stock.
 

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Newsflash, if you put on lighter, smaller wheels, your fuel consumption will go down.
 

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Discussion Starter #9
Newsflash, if you put on lighter, smaller wheels, your fuel consumption will go down.
I knew this but I wasn't expecting an 11% jump going from 17's to 15's!

I mean with how much I drive i could save almost $400 per year running 15"'er's year round.
 

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I doubt that your results from less than a week of driving are indicative of what you would experience driving on those wheels year round, but yes you could potentially save a few dollars by using those wheels for a longer period of time.
 

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I doubt that your results from less than a week of driving are indicative of what you would experience driving on those wheels year round, but yes you could potentially save a few dollars by using those wheels for a longer period of time.
I see what you are saying since it's only been a week. But I'm now up to 2100 miles in that time frame with consistent driving styles and conditions. Will see how it goes but I'm liking the results so far
 

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I saw very similar results when switching from my 18" Michelins (35-37mpg) to my 15" Nokians (39-41). It's also worth pointing out that my Nokians, my Michelin PS3s, and your X-Ice are all LRR tires (to some degree). Not sure about your original 17" wheels.
 

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I doubt that your results from less than a week of driving are indicative of what you would experience driving on those wheels year round, but yes you could potentially save a few dollars by using those wheels for a longer period of time.
Drive the same car, with the same type of gas, in the same location at the same speeds and you can have 10% or greater difference due to: wind, tank fill repeat-ability etc. Why people think they can conclude mpg difference in one or two tanks is ... sad...


Brian
 

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Drive the same car, with the same type of gas, in the same location at the same speeds and you can have 10% or greater difference due to: wind, tank fill repeat-ability etc. Why people think they can conclude mpg difference in one or two tanks is ... sad...


Brian
One or two tanks sad yes. I'm going off of 5 tanks here. 5 full tanks. Actually 8 decent fill ups. Wind...ok I'll give you that one but it's constantly helped or hurt. But with no wind my ug shows 40mpg instant at 70 mph where it showed 35 before. I've used both my gps to adjust for distance actually traveled and ultragauge calibrated to this so I'm not depending on inaccurate gas fills.

My point is.....I put some miles on. I'm telling you guys/gals smaller diameters tires/lighter wheels...one or the other make a difference in mpgs. In my case it's over 10%.

After 96,000 miles of driving my car for work I wish I was driving an se instead of a titanium lol
 

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Drive the same car, with the same type of gas, in the same location at the same speeds and you can have 10% or greater difference due to: wind, tank fill repeat-ability etc. Why people think they can conclude mpg difference in one or two tanks is ... sad...
Brian
Why people jump to negative conclusions based off of what others have tested and proved to be positive is sad. He's reducing weight upon the rolling resistance of the vehicle, by quite a bit. Not only that the contact patch between those two tires with the road is also reduced. If you guys are going to flame pick a better fire [;)]
 

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Why people jump to negative conclusions based off of what others have tested and proved to be positive is sad. He's reducing weight upon the rolling resistance of the vehicle, by quite a bit. Not only that the contact patch between those two tires with the road is also reduced. If you guys are going to flame pick a better fire [;)]
If he's running similar pressure in the tires the contact patch will be about the same. A difference in tire compound and sidewall construction can have an effect on mileage and there are purpose built tires designed to improve mileage, albeit at the expense of handling.

Smaller wheels are likely to be lighter and have a lower moment of inertia which can improve acceleration and braking and may have a very small benefit in mileage, but the mileage effect would be impossible to notice in the tank-to-tank noise. At constant speed the weight and moment of inertia difference would be make almost zero mileage difference.

Again, claiming 10% improvement is out of the question, it just is...


Brian
 

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After 96,000 miles of driving my car for work I wish I was driving an se instead of a titanium lol
Not to hijack this thread but....

I'm starting a new job Jan 1st and my yearly commute is going from 1250 mi to ~22,500 mi. I'm looking for a 2012 Ford Focus as my commuter car, can you expand on your comment? It seems a loaded titanium would be the way to go...
 

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Not to hijack this thread but....

I'm starting a new job Jan 1st and my yearly commute is going from 1250 mi to ~22,500 mi. I'm looking for a 2012 Ford Focus as my commuter car, can you expand on your comment? It seems a loaded titanium would be the way to go...
Though I'm being called either a liar or delusional because of my findings.......;)

Simply because of the tire/wheel size. Sure the 17's and 18's look great but I could have saved almost $1000 in gas costs if I was running a 15" setup full time.

I believe Praton had similar results so now I don't feel so bad. My results may vary this week I know but the weather hasn't turned yet so I should have another ten days to put on some more miles and see where my mpg's are.
 
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