Tires and gas mileage

[wallygetsit]

I have had my Explorer for the last 100,000 miles or so.

My General brand tires that I got from the Firestone recall were needing a replacement. They had about 90,000 miles on them. They were an excellent tire. Fantastic wear, great ride and low noise...as compared to the Firestone Wilderness A/T's.

I opted for some Uniroyal Liberator A/T's. Looked nice and more aggressive. Price was right also. 255/70R16's. Same size as stock.

Since I've had these tires installed. I have lost 2MPG. I drive the Explorer to work everyday... the same way and distance. Like I said, I have driven this route for roughly 100,000 miles.

Before I easily got 19MPG. Easily. It was not uncommon to get 21-22MPG. Now I am only getting 17MPG. (Weather conditions - same before and after install.)

This new tire is more aggressive, but I didn't think I'd see a 2MPG hit in fuel "economy".

If you are concerned about fuel mileage... be careful in which tire you buy.

Anyone else seen this?

 

[Rhett]

I have seen it. But 2 mpg is quite a lot. Make sure they are aired up enough.

Did you do a "chalk test" on them? That will tell you how much air to keep in them, which should be 30-35 psi. If you're running less than 30 psi that will hurt your mileage.

 

[wallygetsit]

I forgot to mention the air pressure thing. My bad.

I always run all my vehicle tires at 40psi. I am pretty religious about that.

The ride is a little stiffer, but the fuel mileage always improves and the tire life always improves. That is probably why the last ones got 90,000 miles.

I used to be a bicyclist, thats why I care so much about tire pressure. It's amazing the difference when peddling a road bike with 110psi versus 90psi.

Thanks for the reply.

 

[kert0307]

ya, i noticed about a 2-3 mpg difference when i went from the stock michilin 255/70R16's to TrXus mt 265/75/R16. I was expecting a drop though due to them being larger. I think it is more due to weight though. The tires i have now are a lot heavier than the others.

 

[Rhett]

I always run all my vehicle tires at 40psi. I am pretty religious about that.

40 psi may be less than ideal for your tread life. Then again, it may be perfect for your truck and your driving conditions. If you search for the term "chalk test" on this site it gets into more detail on that.

 

[Bwana Bob]

When was the last time you checked gas mileage? If your state uses the oxygenated gas in the wintertime, it will drop the mileage about 2 mpg.

Here in NJ, gas mileage is always poorer in the wintertime.


Bob

 

[IAmTodd]

You also need to look at the weight of the tire. This tire could be slightly heavier, but when its rotating, that weight means alot more.

 

[aldive]

The friction produced by aggressive tread pattern can indeed "eat up" gas mileage.

 

[wallygetsit]

I think all you guys are right on the tires... both tread pattern and weight.

Most of my driving is highway so 40psi produces very even wear on the tires are the way across.

I check my mileage at every fill-up. I used to fill out a spreadsheet after every gas up, but now I just calculate it out on the iPAQ.