MPG After Lift/Tires/Wheels....Offroading

So I was averaging 18-19 MPG prior to any mods.

Then I removed the wind dam/skirt. MPG went to about 17-18

Then installed Kings front and back, with Falken Wildpeaks 285/70/17 E Load Range on Method 307 wheels

My MPG dropped to 14-15 (which is fine, as I expected it)

THEN I took it Off Roading for the first time this past weekend and cant seem to recover to 14-15....Im stuck at 12-13MPG, anyone have any insight on why?

 

Countdown to "it's a truck, why do you care" comments in 4... 3...

I'll tell you that I have no skirt (Off-road trim doesn't have one), 265/70/17 KO2s, and upgraded suspension (Icon 2.5" in the front, 2.0 in the back) and I'm the same neighborhood (14-16 average MPG for a tank). You'll get people here with 35s telling you they still get 25mpg, but they drive like my granny no matter what they say.

As far as your drop to 12-13... Are you still on the same tank of gas? Because your MPG on the dash is cumulative for the tank, so if you went wheeling, you probably just skewed it. You should look at your individual trip summaries to understand what you're actually getting for the post-offroad trips.

-Craig

 

Rotational weight from larger tires kill mpgs. Rule of thumb is 10lbs of rotational weight is roughly 100lbs of chassis weight.

 

You’re right! I was looking at the tank fuel economy not the trip! Will test out on drive home! Thanks.

 

Also your computer doesn't know you have bigger wheels and your ODO/Speedo are in error. So it's not giving you real numbers.

Factor in the % delta in tire diameter. You're getting better MPG than your truck thinks.

 

^^ This. Your MPG *will* decrease with bigger/heavier wheels/tires, but the accuracy of your truck's computer and odometer are off as well.

 

Pi*r^2 is your friend.

 

3" lifted on Icons.
32.75" tires.
89 gas.

 

This may be useful for heavier stop and go miles; but, for highway miles a pound is a pound. Newton's first law. Yes, they are harder to spin up; but, once they are spinning they will spin just the same as a lighter tire. They'll also help you to coast farther; this is where you can get the energy you used to spin them back. The more you hit the brake the more energy you waste... true no matter what tires you run.

 

Pi*D for circumference (or 2Pi*R)

 

Seems suprising your mileage is that low. I’m on an almost 3” lift, 16” SCS SR8 Rims (they’re light!) and 255 85 R16’s E-rated. I get between 17-18 MPG’s (I track with the Fuelly app) very consistently on Road. As stated above my actual MPG is better than shown because each revolution of the larger tire is a slightly longer distance traveled.

Circumference = 2(PI)R

Though I’m the interest of full disclosure my commute is about 50 miles a days but no freeway. On the freeway my mileage drops substantially.

 

I get about 16 in town (too many stoplights) and right around 20, 20.5 on highway with my 255/85s, but I do drive like a little old lady. I think I lost more MPG from my roof rack than I did from the lift and tires.

 

I dig those "hole" wheels. Are they hub-centric? Also, what lift?

 

255/85 r16? What lift and any rubbing? Do you think they will fit with my 2" OME lift? That is my favorite tire size

 

They are beautiful! hehe

 

But are they hub-centric? Also, how many inches of lift in the front with those Kings? Any vibes on the steering wheel?

 

I've got a 885/Dakar lift now, but I had no rubbing even without the lift, aside from having to take the front mudflaps off. I use the stock TRDOR wheels. Aside from the limited choice I really think it's the right size tire for most folks in these trucks.

You will need a BFH to persuade the guide brackets for your spare tire though. No big deal, took a few minutes.

 

I believe they are NOT. I haven't measured the lift since install (last Thursday) but should be between 2-3 inches. NO vibes on the steering wheel.

 

What size tire you running?

 

BFH? Big F**kin Hammer?

Also, got a pic of your ride?