Ok i got 295/60/20 toyoo Mt and a 5* tune. The tune helped but man i wasnt excpecting this. I have the 5.0. In just wondering what can help or if I need to consider the toyo at2 BC they are 12 lbs lighter in averaging 15.5-16at 65mph. What u guys getting?

 

I quit using heavy LT tires for that reason. I'm running P275x60x20 Toyo AT2's and getting up to 19 mpg on the highway.





Tires are 33x11.





This was after a short 120 mile round trip.

 

The width of the tire could make a difference in the aero drag on the interstate.

 

You need to consider:

1. Effective gear ratio has changed ( taller) with larger diameter tahrs

2. Static increase in mass

3. Dynamic increase in rotational inertia - FAR more impactful than simple unsprung weight increases - it's a geometric progression.

4. Rolling resistance.

5. Aeros.

MGD

 

PawPaw I got the 5.0 so ill probably never see 19mpg. Ya I love the look but probably will end up doing something different!

 

My previous truck was an '11 Lariat 4x4 with the 5.0 and 3.55LS. Running the same size 275x60x20 Toyo's I averaged 18.1 on a close to 3K mile round trip. Tire is only 43 lbs so it's close to the same weight as the stock Pirelli's I had. My '13 with the Ecoboost and 3.31's only gets 1 mpg better then my '11 did with the 5.0.

 

Just put 285/70/17 duratracs on a 07 5.4 screw 4x4 with 3:55's
Havent calculated it yet but I'm guessing I lost close to 1.5 mpg. Gonna need a tune and 3:73-4:10 just to get it back. Things a big turd now. Not that it wasn't before. I don't care much for fuel mileage though. Have owned nothing but v8's for 13 years now. At least I won't get stuck in wet grass anymore.

 

275/65/20 toyo at 2 looks nice 34.1x11and if im looking at charts right that knock 23 lbs pee tire. Im betting that id gain a 1mpg