MJames26

Im looking to buy a 2018 Ford F-150 with the 5.0. I am wondering what ratio I should be going. I drive mostly highway but a little in town as well.
I want to be putting a bit bigger tire on the truck probably a 33". will the 3.31 be okay and maintain good fuel milage or should I be going to a 3.73?
Thanks.

Bigcat1185

iTrader: (1)

373

Sirikenewtron

If you don't plan on towing much and only plan on going to a 33" tire 3.31 would work but a 3.55 would be a nive in between.

I personally wouldn't get a 5.0 without 3.73's since Ill be towing more often. Even with the 10 speed
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zx12-iowa

5.0 has good midrange and great top end but low end is just ok. so 3.73 gears will help make low end match the good/great midrange and top end. 3.31 will also cause lots more downshifting...

FordDNA

I hated the 3.31 on my 2017 with 35" tires. Traded it for a 2018 5.0 with 3.73.

aspade

Always get the shortest gears you can. At least within the range of what's offered from the factory, the shorter axle has no downside. Shorter gears drive better, the mechanical advantage makes that drive easier on the rest of your powertrain, and the real world fuel economy difference is somewhere between irrelevant and immeasurable.

https://www.epa.gov/sites/production...ng-alpha_0.pdf (see Fig 18 & 19)

acdii

Do not get the 3.31 with the 5.0. There are way too many complaints with how lousy they tow, and the 5.0 is one of those engines that likes to rev high. If it were an EB, much different story as they like to be low in the RPM when cruising, and gets torque down well down low as well. I can show a 2+ MPG difference between 3.15 gears and 3.55 gears with an EB and 6 speed transmission. Go for the 3.73, you wont regret it.

Thugzy

I agree with acdii... 5.0 should always get the 3.73..... the EB's can easily get away with the 3.31, because of the 10 speed

BadAV

The eco's can easily get away with it with the 6 speed as well. I've got 33s on mine and occasionally tow heavy with it. Haven't noticed any negatives at all. I suspect there would be very little real world mpg difference between 3.31 and 3.55. The 3.31 is what was on the lot when I bought, so that's what I ended up with.

rt2bowhunter

I got the 3.73 with my 5.0 2017. I like it theres a fair amount of hills around close to home. It pretty much shifts in 6th and stays there sometimes it shifts to 5th. Driving my wife to the mall its flat driving and 55 MPH i get 22 23 once i got 24 MPG taking the trucks word for it. Most tank full's i'm getting 17 18 mpg i think the No.1 trip gage i haven't touched last time i looked it had 16.7 MPG. Thats over 10,000 Miles of driving Winter warm ups and all.

I tow a 16' Bass tracker boat and i cant tell its back there. The truck just purrs right along. And if i need to get on it, its got plenty of get up and gone . I haven't had much experience with ford motors being as this is my first f150. But i about gotta agree id get the 3.73.