JC-85

Hello guys, I own a 2017 F150 Supercrew Lariat 3.5 Ecoboost 4x4 with a 10 speed trany. It is stock with the exception of a 2.5" leveling kit and I want to change from a 275/55/R20 (32") tires to a 275/66/R20 (34") tires. Do anybody knows if I'll need to regear to a higher ratio like a 4.10 or 4.56? I do light off road and rearly tow something. Have someone had changed their tires for something similar that can share the experience?

smokeXC

I have basically your set up in a King Ranch. +2" RC, 275/65R20 BFG's.
On the stop watch did you lose some, Yep. They are a heavier tire.
Does it feel like it to me, Nope.
I do light hauling or towing and some easy trips to the cabin, NO problems at all.

5.0_FX2

I went with the same sized tire on a 5.0 and noticed no real power loss. With the torque of the 3.5 ecoboost you more than likely won't notice just as smokeXC suggested. Pull the trigger. Lol.

SPOAT

You didn't mention your rear ratio.

If you have a 3.55 rear, the change would be comparable to going to a 3:30 in approximate percentages.

Hardly noticeable with these powerful motors and multiple gear transmissions.

You will notice the tire weight in braking. You'll be giving more throttle from a stop but it's not that noticeable.


Pecked out on my iPhone.

redraiderford

You dont need to regear. My brother has the 275/65/20s on his 09 F150 and it does just fine

NASSTY

Enquiring minds would like to know what gears the OP has.

gouldje

I got same tires with 3.55 gears, doesn't lock up 10th gear as much now, dropped 2-3 mpg's

tvsjr

Make sure you're reprogramming the computer with Forscan to adjust the shift points.