Hello i have 19 rav4 hybrid with 17inch wheel oem 225/65/17 25 pounds
I want to switch for 20 inch wheel 27 pounds 245/45/20

I do 40 000 miles by year... gas millage is really important for me! You think iTs gonna be the same or worse??

Thx JT

 

Worse. Heavier with a higher angular momentum. Will take more energy to spin them up. You may also be limiting your tire choice to less optimal LRR choices.

Your speedo will read 0.6% low.

 

it's not going to make a difference on the mileage,, but the ride will be more rough.. as you have less side wall to deal with..

 

You are going to lose some simply due to the wider tire... Cross sectional area and drag coefficient.

You can't change physics. Learned that the hard way long ago with K5 Blazer. Lift kit, bigger wider tires and I doubled the horsepower.

Lost top speed.