Change in mileage

I've had my '23 SR 4x4 Tacoma for almost a year and had been consistently getting 21 to 22 mpg for my daily driving. Last month I had a level kit installed and moved from the stock 245/65/16s to Hankook Dynapro ATm's in P265/75/16s. My daily mileage has dropped to 20 mpg. I checked my tire pressure and all 4 tires were inflated to 34 psi. This seems a bit of an extreme change for such a minor mod to the truck. I saw a thread on this forum regarding the Dynapro tires and noticed that other users were running 38 psi. Anyone have any thoughts on the change in mileage?

 

Lift and tires means, negative air pressure (drag), rolling resistance increase, diameter of tire increase leading to longer final drive (less torque) and heavier tire as rotating mass.

Don't set P tires higher than 35, it wont get you the mpg back.

Step back, enjoy how the truck looks and stop worrying about mileage.

 

You changed your suspension, you changed the make and size of your tires, probably increased unsprung weight, all can factor into your mileage. In the scheme of things, going from 21–22, down to 20 is not that much of a change and depending on how you're calculating MPG your odometer might be thrown off by the difference in tire size. I have seen mileage changes like that simply due to the new tires having different rolling resistance from stock.

You made too many changes at once to pin it to any one factor.

 

I had and now get those exact MPGs after going from stock 245/75/16 to 265/70/16 duratracs with no lift or suspension change.

 

Welcome to TW! I wouldn’t consider a 1 mpg drop to be extreme by any means. Enjoy your 20 mpg, I get about 13-15 mpg with my truck.

 

Welcome!

 

Youre looking at it wrong.

Yes, the "miles per gallon" on your ODO is different, but you are probably covering the same DISTANCE with the same tank.

https://www.tire-size-calculator.info/index.html?&1tw=245&1ar=65&1dia=16&2tw=265&2ar=75&2dia=16

Your speedo at what used to be 60, is now 54. Your tires are covering more distance with each rotation. Less miles are showing on the ODO, but you are covering same distances you drove before.

Yeah the extra weight might lose some mileage, but youd need to factor in the speedo correction for the actual loss.

The calculator says its a 10% difference. If you had been getting 200 miles to your tank, and now are seeing 180, then thats 10% loss, but because of the tires give-or-take.
(I think thats right)

On the plus side, less miles will add up on the ODO!