Thread: Choosing a Tire
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Old 09-25-2011, 06:55 AM   #7 (permalink)
HighMPG
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Join Date: Sep 2011
Location: California
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Super Duty - '12 Ford F250 Super Duty XLT Long Bed Super-Cab
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Quote:
Originally Posted by oil pan 4 View Post
I am not a believer when it comes to tiny tires for MPG. I can not find any one that lost MPG by going with a slightly taller tire (less revs per mile).
Wider tires offer less rolling resistance with the same load.
At some point drag losses which increase by a factor or 4 every time your speed doubles will over come the lower rolling resistance which doubles with speed. I don't know where that point is, but I think it is roughly around highway speed for a car.
With a car you should be able to aeromod your way around the wider tire drag problem.
Also the idea of a small contact patch with a hard rubber compound does not inspire confidence with me.
I did the worst tire swap imaginable on my truck and I gained a barely detectable boost in MPG, that was going from a P235/75R15 that weighed about 26lb to a 2 inch taller 31x10.5R15 that weighed about 40lb. Both tires were made of hard compunds known for lasting over 60,000 miles.

When it comes to tires I have 2 rules.
#1, no tires made in china. Their quality control is garbage.
#2, no firestones, past performance is indicative of future results.
I like that imput
Well I want OEM size tires and guess I will try them out.!!! anyways! haha
I had to choose between the two and FIRESTONE is last on my list! lol

I will make a comparison against my used, old, Radial X and the new Kumho's.
I actually only need 2 tires but would like to get a good comparison and run a full set. I may try another brand in 175/70/13 if I am not happy with the only real 155/80/13 tire left on tirerack!
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