Who's towing with bigger tires ?
04-09-2016, 01:38 PM
#1
Member
Thread Starter
Who's towing with bigger tires ?
I haven't towed with my truck yet so not sure what the difference is between towing with stock tires 275 55 20 vs bigger tires 305 55 20. I have a 15 lariat sport with 3.5eb 355 gears. The truck had upgraded 305 55 20 Mickey Thompson tires with a 2 front level when I bought new last September. Would like to hear what others think about how the truck tows with bigger tires. Thanks
04-10-2016, 03:45 PM
#2
Grumpy Old Man
The 305s are taller than the 275s, so you'll have less engine power and torque. But not much difference. Here's the math:
P275/55R20 have 652 revs/mile.
LT305/55R20 have 622 revs/mile.
652 minus 622 = 30, divided by 652 = 4.6%
So your 3.55 axle ratio with 305 tires will "feel like" a 3.39 ratio with 275 tires.
If your speedo/odo/tripmeter were correct with 275 tires, they will be "slow" by 4.6% with the taller tires.
IOW, 75 indicated will be an actual 78.45 MPH on Officer Bob's radar gun.
400 miles on a tank of gas will be an actual 418.4 miles for manually computing MPG.
With your EcoBoost drivetrain, that's not enough difference for you to even notice
P275/55R20 have 652 revs/mile.
LT305/55R20 have 622 revs/mile.
652 minus 622 = 30, divided by 652 = 4.6%
So your 3.55 axle ratio with 305 tires will "feel like" a 3.39 ratio with 275 tires.
If your speedo/odo/tripmeter were correct with 275 tires, they will be "slow" by 4.6% with the taller tires.
IOW, 75 indicated will be an actual 78.45 MPH on Officer Bob's radar gun.
400 miles on a tank of gas will be an actual 418.4 miles for manually computing MPG.
With your EcoBoost drivetrain, that's not enough difference for you to even notice
