Tire rolling resistance (copied from another forum).

[Rawze]

I invested in 2 sets of drives. M710's and R283's (16-ply). We had the bright idea to use theR283's in the summer because they have a lower rolling resistance than the M710's. Then use the M710's in the winter.

The R283's did improve the fuel mileage about 0.3 mpg above the M710's. The only problem is that they would spin out way too often in gravel and in parking lots. They also got dangerous in heavy rains. - They had to go, they were dangerous in my book.

We went back to the M710's all year around. We have been using the R283's for steer tire replacements as we need them.

Personally, I think the concept is novel, but ...

A) Dangerous/Risky for a highway truck.

B) If your down in the 6 - 7 mpg range, it is NOT YOUR TIRES that is going to get you any significant gains. It is likely your driving and other things you need to work on long before spending a lot of money on those last few tenths by running lo-roll steers on the back end.


That is my own experience any ways.

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(10-28-2018 )schISM Wrote:  A few weeks ago I swapped out my 726EL’s that were down to 5/32’s to brand new XDN2’s. At the same time I replaced the drums/brakes and recalibrated my speedometer(went from tall to low pro). I figured my 7 mpg average would lose a few tenths, no big deal but I’m struggling to get more than 6.2-6.3, and sometimes less than 6. I’m really thinking next spring of getting some straight treads and having two sets of tires. Bad mileage sucks.

BTW: 726's are horrible on fuel mileage. The extra bit of tread life they have is NOT worth it.

Your speedo and engine tire size settings will not effect your fuel mileage. You should always be checking your fuel mileage by way of the fuel pump and a calculator.

Whenever we replaced tires and from a worn out 5/32's or so tread depth to a brand new set of the same exact tires, we loost about 0.7 mpg for the first 80k miles or so while they break in. That is a lot, so we decided we need to run our tires as long as down to minimum absolutely possible this go around. We get about 450k miles or so out of our drives so thankfully we have only had to suffer that fuel mileage hit a couple times so far.