ALH What to check next? Only 36-38 mpg at 65mph!
- Thread starter juneau10
- Start date
KCCats
Veteran Member
Here is what I have found so far.
I put my wife's tires 195 65 15 on and ran a few tanks of fuel. 41.8mpg!
With my 205 70 15 all I could get was 39!
Now I measured the circumferences 195 was 79 in and the 205 was 84 or about 5 percent.
So if I figure an additional distance into my calculations of 5% I go from 39 to 42!
I put my wife's tires 195 65 15 on and ran a few tanks of fuel. 41.8mpg!
With my 205 70 15 all I could get was 39!
Now I measured the circumferences 195 was 79 in and the 205 was 84 or about 5 percent.
So if I figure an additional distance into my calculations of 5% I go from 39 to 42!
GASDAG
Veteran Member
- Joined
- Feb 2, 2013
- Location
- Columbus, OH
- TDI
- 2002 Jetta GLS 5MT Sedan Silver, 2004 GMC Sierra i.e. no need for a wagon
Yeah I got the same 205/70 tires... It's actually a 5.3% larger tire circumference, so when you go to fill up, and your trip odometer says for example 500 miles, you multiply that 500 times 1.053 to get your corrected actual mileage. Then divide that number (526.5miles) by the number of gallons you put in.
KCCats
Veteran Member
Exactly!