Browe4140

I have a 2015 f150. It had 265/60/18 tires (30") put 305/55/20 tires (33.4") on now. Lost around 2.5 miles to the gal. It has 3.31 gears. Thinking about 4.10 gears. I'm on the road around 700 miles a week. I have a camper that's 8,000 lbs. I've only pulled one time so far. Want to know if anyone has done the 4.10 gears and the pro and cons. I was getting 21 to 22 mpg. Now around 17 to 18. Want my get up and go back but don't want to kill my mpg. Thanks in advance

HacksawMark

While your tires are about 8.76% larger diameter, they are also 15% wider. Comparing mpg from your factory setup to the current one you have now is like comparing apples to oranges. Keep in mind your speedo and odometer will be off. With the new tires, 65 mph on your speedo will really mean 70.7 mph. To obtain your true mpg, add 8.76% to your odometer miles and then divide by gallons used.

https://www.discounttire.com/learn/tire-size-calculator

Keep in mind, you will most definitely lose additional mpg with either gear swap.

Browe4140

Already got speedo set right with a programmer. And my mpg is 17 to 18 mpg. So it's 2 to 3 mpg less then before. Just lost some power because of bigger tires. Want to get the power back. I'm fine with the mpg I'm getting now just don't want to get any worse mpg then now.

FirefightinFX4

What powertrain?

That's going to be the deciding factor for me regarding gears. 4.10s in an ecoboost with 33" tires is going to suck down gas like a fat kid drinking a slurpee.

ABolt

The Raptor comes stock with 34" tires, a 3.5L EB, and 4.11 gears.

It's rated at 15 city and 18 highway, which is better than my old 5.4L 2-valve that had only 265 hp.

Fuel economy on these big vehicles is very subjective...

Toprat

I've got a 2016 5.0 on 35's and just did the gear swap from 3.31's to 4.09'. Definetly brings the performance back. My daily driving mpg is actually better with the gear if I don't keep my foot to the floor. I think it was worth it in my case.

Browe4140

I have the 5.0 , I've already got a cold intake, true dual exhaust and a SCT x4 programmer. Just want to do the gears now

Iamraiderpower

large offroad tires and good MPG shouldnt be in the same sentence. I would ditch the tires before swapping gears

Browe4140

Not getting rid of tires!!!!

Iamraiderpower

well you wont be getting MPG back then