bigger tire for improved mpg?

Question

Have 245/75r16 tires on vehicle now........want to go to a 265/75r16 tire on a E-250 cargo van ,gasoline engine, will this help increase my mpg? if so how much? serious answers only

Im looking at highway speeds on this, not city for fuel economy , the 265 turns 33 revolutions less per mile than a 245 does....i believe this should save fuel somewhat "more" at highway speeds.

Answer 1

There's really not enough height difference between a 245/75 and a 265/75 tire to make a serious difference in fuel mileage on your E-250, but it's been my experience that going to a taller tire may actually hurt fuel mileage. The taller (and wider) tire not only offers more rolling resistance due to increased tire contact with the roadway... It also requires more engine torque to turn the taller tire, which means your engine is going to have to work harder to move the truck down the road.

If you still want to change to the bigger tires, make sure your tire shop recalibrates your speedometer to give you accurate readings with the taller tires.

Answer 2

First of all, the only difference between the two sizes is the width. Both are the same height, 75 on a 16" rim. Think about this. The higher the tire wall, the weaker it is so it tends to bend outwards more. This creates more drag. The shorter the tire wall, the stiffer it is, so less drag. And if you have a small tire that turns completley compared to a large one that does the same, the large one will go further, but weighs more. Why do you think race cars have beefy tires in the rear. The smaller the tire, the less drag it has, and weighs less but it has to turn more. So basically you have to find an equilibrium to get the most out of it. Like Tweedasheetz said, go with the original size, it is what it is for a reason.

Answer 3

One more thing to remember. A larger tire might turn fewer revs at a specified speed but your speedometer won't know it. Your speedo could be reading 65 with either tire, but you actual road speed would be different. The taller tire would have you going faster at "65" than the other tire and this will increase your wind resistance, etc.

Answer 4

the engineers who design these carsgive them tire size for a reason. They are not just pulled out of a hat. If you want gas mileage, tire size is not your option, although a larger tire will change your revolutions, it will also change your accelration. I would recommend a throttle body spacer and a k and n filter, these will make a difference.

Best of Luck!

Answer 5

Fordman is right, more rubber on the road is more rolling resistance and this means more fuel. Pumping the tire harder, but do not exceed the max on tire will improve mileage.

Answer 6

You are going with a wider tire, you will have moe contact area and you will have more drag and the MPG will decrease.
I had and IH Scout II drop 3 mpg after going with a larger tire.

Answer 7

i own a repair shop,and it will help increase it,i don't know how much,no one knows this we don't know what kind of mileage your getting now,but it always helps to add a little bit bigger tire,the engine and transmission have to turn less rpm,s to make these go ,so naturally your going to get a little better mileage,you,ll have to try them and see,but they will help it,good luck hope this helps.

Answer 8

with bigger tires the car get worse gas mileage. The smaller the wheel the better it gets , BUT the smaller the tire yyou increase your chance of loss of control and rollover