Best tire pressure for best gas mileage?

xDieselxTunerx

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Whats the best psi to run my tires for the best fuel milesage? I have 205/55R16's right now im running them at 38psi. Is that perfect or too low?
 

kwong7

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Mar 25, 2004
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Southern Caifornia
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2001 Golf GLS TDI / White
I had my 225/45/17 Michelin Pilot Sports up at 42/40 PSI. Over 50K miles, I noticed the middle of the tires were wearing out faster than the shoulders. Over the last 15K miles, I've decreased the pressure to 34/30 PSI and noticed no decrease at all to fuel economy (still getting 45MPG), better braking, traction, less tire squeal, and no more oversteer when taking turns like crazy.

When I had my stock 195/65/15 Michelin Energies, they seemed more sensitive to pressure change. I say this because I noticed a 2MPG gain when I upped the pressure from 30 to 44PSI. This leads me to believe that every tire compound and design will yield different results.

After 65K miles on my Pilot Sports (great tire btw), I'm going to try out the Pilot Sport PS2s. Best review from Consumer Reports and seem to have good reviews from users on tirerack.com. I'll note any fuel economy vs PSI differences.
 

Mike_Van

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xDieselxTunerx said:
Whats the best psi to run my tires for the best fuel milesage? I have 205/55R16's right now im running them at 38psi. Is that perfect or too low?
For max. MPG, many folks here run 85% of the max. PSI indicated on the tire sidewall, so this value is specific to your tires. This value is usually higher than the suggested values indicated by VW (in my case, in the fuel door).
 

MBoni

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Atlanta, GA
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Just a caution:

Tire pressure usually creates a tradeoff between traction and friction. High pressure provides less friction (therefore better MPG), but also less traction. If you are planning on doing any driving where you may approach the limits of your tire's ability to stick to the road, like in twisty mountain roads, you might want to be closer to the VW recommended value.
 

tditom

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xDieselxTunerx said:
Whats the best psi to run my tires for the best fuel milesage? I have 205/55R16's right now im running them at 38psi. Is that perfect or too low?
The best economy will be acheived with least rolling resistance, which would be acheived by the highest pressure the tire could handle. This wouldn't be the safest for all road conditions, though.

You might consider going to a narrower tire if you really want to have an impact on fuel economy.
 

kwong7

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Mar 25, 2004
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Southern Caifornia
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2001 Golf GLS TDI / White
I guess my previous convoluted point was that the relationship between tire pressure and fuel economy is not perfect one-to-one linear relationship. There's a point when more PSI in the tires will show a substantial benefit. I've noticed this with my Michelin Pilot Sport tires above.
 
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