Larger Tires w/ 2.7 Eco & 3.15 Axle Ratio?
12-12-2017, 05:39 PM
#1
Larger Tires w/ 2.7 Eco & 3.15 Axle Ratio?
I recently ordered a 2018 2.7L Eco w/ 3.15 axle ratio because I wanted to maximize my MPG. I am also looking at larger tires but hadn’t realized larger tires cause a performance hit on the gear ratio.
If I upgrade my stock tires which are 31.9” to 33.0” tires, do you guys think I’ll need to regear to 3.55? I was told by my dealership that since the 2018 has a 10-speed tranny, I should be okay without regearing? Thoughts?
If I upgrade my stock tires which are 31.9” to 33.0” tires, do you guys think I’ll need to regear to 3.55? I was told by my dealership that since the 2018 has a 10-speed tranny, I should be okay without regearing? Thoughts?
12-12-2017, 05:51 PM
#2
Senior Member
No you will not need to re-gear, 33's will be just fine. They will be a little heavier and you will lose a little MPG and performance, but your truck will handle them just fine.
12-12-2017, 09:24 PM
#3
Senior Member
A 3.15 gear ratio would be unacceptable to me even with stock size tires. Going to 33" tires effectively means you have 2.89 gears. I'd go straight to 3.73 gears at a minimum. That would effectively leave you with 3.43 gears with the bigger tires.
12-12-2017, 09:46 PM
#4
Two polar opposite comments. 
Perhaps I should also note that I’ll never tow anything and will haul minimally. Anyone else done a similar tire size increase with 3.15 gears? I’m curious to know how noticeable the performance hit is and if noticeable, if it’s bearable.
Perhaps I should also note that I’ll never tow anything and will haul minimally. Anyone else done a similar tire size increase with 3.15 gears? I’m curious to know how noticeable the performance hit is and if noticeable, if it’s bearable.
12-12-2017, 11:15 PM
#5
I've got 35" on a 2017 2.7L 6spd...6" lift....never changed gear ratio (but I live in flat-ish Houston)...no issues whatsoever, went from 700 miles in a tank of gas to just over 600 miles (36gal tank)
12-13-2017, 05:49 AM
#6
Trending Topics
12-13-2017, 08:39 AM
#9
Senior Member
I agree with 3:73 at a minimum. Every truck I have ever driven with large tires and high gearing was an absolute dog.
12-13-2017, 09:44 AM
#10
Senior Member
The answers here are going to be split down the middle. Half will say you'll be fine (me), and the other half say to re-gear which I think is completely unnecessary. If you have the money for a re-gear, I suggest you upgrade to your 33's and see how you like it. If you feel like the performance or fuel economy isn't up to your standards, then pay for a re-gear. Like Dustoff24 said, he has 35's with a 6" lift and it's fine.