285/70/17 poor mpg

Ive searched the forum and couldn’t really find anything, but is anyone else experiencing very poor gas mileage with 285/70/17 tires? I can’t seem to get over 14mpg even with freeway driving. Truck specs are 2017 dclb SR5 4x4, 2.5” Kings, wheeler aal pack, leer shell, Falken wildpeaks on method wheels. Located in southern California and I’m not driving with a heavy right foot. I’m usually cruising at around 70-75 on the freeway.

 

Well that is a considerable size difference over stock tire height so strike 1, and I am sure it is an E Rated tire so strike 2, and the weight of a shell is strike 3. I have 265/70/17's on mine with a 3 inch lift and get 16 all day everyday.

 

Only 2 strikes they are standard load rating.

 

A 285/70 is a heavy tire, especially E load. Then you add the weight if a shell. Yea, your mpg prob is crappy. I had the same thing on my last tacoma with the addition of an Allpro front bumper. I only saw 14 mpg with a/c off and going downhill.!!

 

E is not a standard load rating

 

Remember your odometer will be off. Multiply it by 1.06 to account for the tire size difference if you haven't.

 

I must be mistaken then. On falkens website they show either a SL rating or E rating. The side of my tires show SL not E.

 

Are they P-Metric or LT tires?

 

Hmmmmmmmmmmmmm never seen before, but I would imagine they are still a lot heavier than stock

 

They are P metric

 

I 100% agree they are much heavier than stock, especially combined with the method wheels. Just wasn’t expecting 14mpg. Oh well, at least it looks good.

 

14mpg on 285s at 75mph is doing really well, especially with winter gas.

 

What load range does it say. E is 10 ply. 2plys for every letter.

 

Rotating weight robs gas mileage an HP faster than dead weight.

 

that tire weighs just under 52 lbs - the LT tire weighs 59 lbs. It's 2 prong - heavier tire and wider more aggressive tread robs mpg. Some guys are running skinnies and not taking as big a hit in MPG even though 33 inch tire and heavy. My guess is winter gas is also contributing the drop. The shell did not affect my mpg as far as i could tell.

 

70-75 mph translated in 33s is 75-80 in actual speed. You’re burning up more fuel cruising at that speed.

If you cruise 60-65mph, you can get 15 (maybe 16mpg) because actual speed is 65-70

 

The 70-75 is going off of my phone gps speed. My odometer is reading 65-70.

 

I get 14.5 on a regular basis. Longer drives of an hour or more I do better, but I think my best right now is 17-18 tops. Exact same tire you have but the trd sport wheels.

 

Truck looks good. Long beds rule!

 

yeah i average around 15 with 285s. highway i can get up to high teens. that's the compromise.