gas milage / bigger tire ??

[Falls]

OK ,

I've check my gas milage which I do once in a great while just to make sure the truck is in check.

I drove 186.6 miles and used 11.4 gallons of gas = 16.3 mpg.

I have tires that are 1" larger than stock (3%) larger.
265/65/17 vs 265.70/17

Since I've never figured out how to calculate the add'l 3% I was wondering if I just add the 3% to the miles traveled .

186.6 x 1.03 = 192.1 actually traveled . Correct or not ?

If thats approx. correct then I would be at 192.1 miles and 11.4 gallons used = 16.8 , correct or not.

This is strictly city and some rural driving to get home . I have 1 15 min. stretch at 50 mph. I also am NOT a light footed driver by any means. (06 V8 4x4 running Revos 265/70/17).

On another note my on board which I never found to be way , way off like everyone says showed my avr. mpg at 16.7

Sorry for such a basic grade school math ??? I'm in a little fog this am , from not sleeping for 2 days .....lol.

 

[gqllc]

I checked my odo compared to GPS and I am at a 5% difference. Odo reads 9.5 miles and GPS says 10 miles. So 17.79 plus 5% = 18.72mpg...not great but better than 17.79. I have 265/70/17 revo's...Those are highway miles and I drive like a grandma! I also have the V6

FALLS..your math is off..
186.6 divided by .97=192.37 which is the same as 186.6 PLUS 3% divided by 11.4 = 16.875mpg

 

[Falls]

I checked my odo compared to GPS and I am at a 5% difference. Odo reads 9.5 miles and GPS says 10 miles. So 17.79 plus 5% = 18.72mpg...not great but better than 17.79. I have 265/70/17 revo's...Those are highway miles and I drive like a grandma! I also have the V6

FALLS..your math is off..
186.6 divided by .97=192.37 which is the same as 186.6 PLUS 3% divided by 11.4 = 16.875mpg

but thats what i came up with ? i'm not following .

 

[jrs2]

There are calculators on the web that show effects of different size tires in speedo/odometer readings.

One's at http://www.onlineconversion.com/bigger_tires.htm

 

[CJ3Flyr]

186.6 x 1.03 = 192.1 actually traveled . Correct or not ?

Yes, that's how I do it.

My on board computer is good sometimes, not so good others. What seems to affect the accuracy is how many starts I make. The longer my drives without shutting the truck off the better.

Another factor is the pump. All pumps are going to click off at slightly different level of "full" due to variations in flow rate into the tank. It takes many tries to get a true & accurate number. .3 or.6 gallons can really change the calculation.

gqllc's 5% is probably correct. I have stock tires and my odometer seems to under report by 2.8-3.0% when compared with my GPS. The tires are worth 2-3% so his 5% makes sense. :cheers:

 

[gqllc]

LMAO...SORRY FALLS.....It should have been your math is ok..It was a typo..LMAO..

 

[Falls]

I happy with it anyway , I usually don't figure it out except a few times a year to make sure everything is cool.

Not bad for a full time 4x4 v8 city driving with a heavy foot.

We are still on winter blend fuel here too , so I will get an increase when it switches over.

Thanks guy's