Bigger tires= Better MPG

[MoToRNecK]

So i installed a new set of 235/75/15 tires on my little 2wd ranger which has 3.45 gears and factory 205/70/14? tires well 25 inches tall to a 28 inch tall tire I just did my first fill up and crunched the numbers on it i went from 24 mpg to 26 mpg how about that?

 

[85_Ranger4x4]

Before or after you corrected the speedometer?

 

[straycat]

Before or after you corrected the speedometer?

^^^What he said. You are a bit off in your calculation. Your gear ratio will also be slightly off with even 2-3 inch taller tires. Slightly wider tires also reduce hp and gas milage. If you did a dyno run with the stock tires and then another dyno run with the taller tires you will notice a drop in hp.

 

[Rose2300]

Your clutch will hate you with that tire size/ gear ratio combo. thats what I had on my 95 2.3, I put 30x9.5-15's on (about the same as 235 75 15) and within a year my clutch was nearing it's death, just from normal city/highway mix driving. itll wear off quicker if you plan to go off road a lot, you will be riding the clutch more and more.

 

[MoToRNecK]

this would be after the speedometer and odometer correction the speedo is off now by 12% as the tires with being 3 inches taller 276.6 actual miles and 10.5 gallons of gas

and the tires that were on the truck were like a 215/60/14 or something like that on the back they seemed a bit wider than the 235s i think because they were a car tire they made more contact surface on the road these tires are a heavier load rating and less foot print on the ground

 

[straycat]

this would be after the speedometer and odometer correction the speedo is off now by 12% as the tires with being 3 inches taller 276.6 actual miles and 10.5 gallons of gas

and the tires that were on the truck were like a 215/60/14 or something like that on the back they seemed a bit wider than the 235s i think because they were a car tire they made more contact surface on the road these tires are a heavier load rating and less foot print on the ground

Sorry, but no way are you getting better gas milage. All of us know better.

 

[daniel3507]

this would be after the speedometer and odometer correction the speedo is off now by 12% as the tires with being 3 inches taller 276.6 actual miles and 10.5 gallons of gas

This confuses me. The original calculations were done after the correction but the speedometer is still off by 12%? So there have been no corrections to speedometer? If you havent corrected the speedometer there is no way to calculate your mileage with any kind of accuracy.

 

[Ryannn]

Sorry, but no way are you getting better gas milage. All of us know better.

 

[shane96ranger]

This confuses me. The original calculations were done after the correction but the speedometer is still off by 12%? So there have been no corrections to speedometer? If you havent corrected the speedometer there is no way to calculate your mileage with any kind of accuracy.

I think he's saying he's calculated it's off by 12%, and in turn calculated his mileage as such.

I agree, no way you could get an accurate measurement without actually correcting the speedo.

 

[shane96ranger]

this would be after the speedometer and odometer correction the speedo is off now by 12% as the tires with being 3 inches taller 276.6 actual miles and 10.5 gallons of gas

and the tires that were on the truck were like a 215/60/14 or something like that on the back they seemed a bit wider than the 235s i think because they were a car tire they made more contact surface on the road these tires are a heavier load rating and less foot print on the ground

What are your other specs on the 235's? I get a 3.91% difference with a 235/60/14 in comparison to the 215/60/14.

Where did you come up with the 12% figure?

 

[6.2]

Makes perfect sense if it was highway miles. If it was city, no way. But highway, I 100% beleive it.

 

[MoToRNecK]

because i took the actualy measurement of the tire on the truck wich was 25 and the tires i put on the truck which came to 28 inches high 3 inch difference is 12% more than 25 inches. and yes 90% of my driving is highway i drive a mile to the freeway and 30 miles to work all highway at 55-60 mph

 

[killj0y]

Well I'm gonna do my calculations at the end of this month. I Sibby have a working odometer, speedo works great though. Anyways I'm gonna use GPS on my phone should be fairly accurate up to a few yards good enough for me anyways.

I just wanna know how bad it is lol.

 

[killj0y]

Got a smartphone? I'm sure you could do the same thing. Then you know for sure since GPS could care less about your tires and gear ratio...lol

 

[MoToRNecK]

it really is pretty simple the slightly larger tires allow for lower rpms on the freeway using less gas without having to turn too much more weight the distance compensates for the reduction in power i dont jump on it too often i drive like a sane person quick shits and dont do 70 mph all day long