# ? for those that went from 16" to 17" or 18"



## cbr954 (Jun 12, 2011)

If you went from oem 16" steel wheels to 17" or 18" aluminum, what affect if any did you see on your mpg?


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## 72buickgs (Mar 20, 2011)

if u went from stock 16 to eom 16 or 17, aren't the diameters of the tires basically equal due to the change in aspect ratio? i would think that your mileage should improve because u went from steel rims to aluminum and lighter weight tires.


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## shawn672 (Oct 31, 2010)

fuel economy wont change very much, as 72buick said, the overall diameter is the same. you might carry an extra pound or two rotational mass


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## osiris10012 (Feb 4, 2011)

from what i have seen in the past it seems like alot of the aluminum aftermarket wheels are pretty close to the weight of steel wheels..you would have to spend quite a bit of money for a really lightweight wheel...i also agree that the difference would be so little you probably won't notice much difference


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## cerbomark (Dec 13, 2010)

i went from steel 16 s to factory alum 17s and think I lost 1 or 2 mpgs.. The 17 s are heavier( not sure how much) and the tire is also bigger and wider and has more drag due to the wider tire. I think the overall weight might be more than a lb or two. When I swap back over for winter I ll weigh them both.


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## 70AARCUDA (Nov 14, 2010)

FYI -- below are the engine revolutions (N) at test vehicle speed (V) of *50 mph* for the different wheel/tire combinations from the GM / EPA test data sheets:

N/V - for Cruze/*Eco* A6 models with 3.87:1 axle
38.5 - P215/60R*16* Firestone
38.3 - P215/55R*17* Goodyear (*Eco* std tire)
38.8 - P225/50R*17* Continental
38.8 - P225/45R*18* Michelin

N/V - for Cruze *Eco* M6 models with 3.83:1 axle
31.0 - P215/60R*16* Firestone
30.8 - P215/55R*17* Goodyear (*Eco* std tire)
31.3 - P225/50R*17* Continental
31.2 - P225/45R*18* Michelin

N/V - for Cruze LS models
38.5 - P215/60R*16* Firestone (A6 w/ 3.87:1 axle)
38.7 - P215/60R*16* Firestone (M6 w/ 3.94:1 axle)
38.8 - P225/50R*17* Continental (A6 w/ 3.87:1 axle)
39.0 - P225/50R*17* Continental (M6 w/ 3.94:1 axle)
38.8 - P225/45R*18* Michelin (A6 w/ 3.87:1 axle)
39.0 - P225/45R*18* Michelin (M6 w/ 3.94:1 axle)


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## Senistr (Jul 28, 2011)

It also depends on the pattern on the actual wheel itsself. If you get a 5 spoke wheel like I did, the aluminum wheel will be lighter than the factory because it's less in mass and less on material, as well as using a lighter material to make the actual rim, so yes, you can gain a small gain in MPG OR lose some depending on the type.


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## perlionex (Mar 10, 2011)

I switched from the stock 16" (alloy, but heavy) to lighter 17" rims.

However, main reason I did so (apart from the fact that it looks nicer) is that I can run 225-width tyres instead of the stock 205-width, which gives me more traction when cornering at the track. Acceleration is also improved as the overall wheel will weight less.

That said, FC will probably suffer a bit, still. Although the entire wheel is lighter, and the overall wheel rolling diameter is kept the same, the wider tyre means the tyre is softer and there is more rolling resistance (of course, the fact that I run Toyo T1Rs doesn't help, either).

In the end, it's what you're looking for. I wouldn't recommend 18", but I think 17" can still give you a good trade-off.


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