bigger tires less mpg? What's your experience?

I'm running 285/75/16 Duratracs. Negligible difference in mpg from stock BFG Rugged Trails, maybe 1 mpg difference if that. I have a suspicion that those who cite a more siginificant mpg loss from bigger tires are forgetting to make a correction for the added tire circumference in their mpg calculations. You just need to look up the spec charts of the tire manufacturers to find the true outside diameter. Using my Duratracs as an example, the difference in circumference between stock Rugged Trails and 285/75/16 Duratracs is 8%, therefore you need to add 8% to your odometer readings before you do the mpg calculation.

 

when you say that you are taking into consideration the increase in the circumference in your tires and factoring that into your mileage calcs?

 

is your odometer calibrated to guage the larger circumference of the tires? How do you measure your mpg after you upgraded your tires?

 

I should add that the 1-2 mpg loss I stated above is with 90% highway/5% city/5% OR driving. These tires are heavy (E-range Toyo OC M/T) and I do have to give it more go juice off the line than I did with stock. If I was doing more start/stop city driving then my dropoff percentage would probably be worse.

 

guys you do have to keep in mind the circumference and factor that in to your readings. Otherwise you're misleading ppl. Odometer readings are not accurate if you up ur tires and do not tune your odometer to read the upgrade.

 

13 mpg after correction. 12.5 mpg without 17 before so almost 25% lost. Its worse on highway mileage since the rpms do not matter for fuel efficiency, contrary to the lies you will hear that say they do.

 

I knew it was no 4x4 just looking at the mileage.

 

I am torn on this topic and keep reading post after post. My new truck should be here tomorrow and I want to swap the BFG trails right away so the shop gives me top $. Really want the look of the 265 75 over stock 265 70 but prefer not make mpg less. BFG 265 70 stock weighs 38lbs and is semi aggressive tread. Firestone Destination AT 265 75 is 42 lbs and inch taller. Destination isn't too aggressive for an AT. Estimates on mpg loss? Anyone make same change?

My new ride will be 2013 dbl cab trd or

Thanks and nice to be back...been taco less since 2010 when I traded my 2007.

 

I get better gas mileage with a one size up tire I was running 265/70/17 on my last Tacoma and increased mileage on freeway cause it dropped my RPMs crusing at 75mph with stock tires I was sitting at 2300 rpms with the 265/70/17 I was 2100 rpms so made my mileage better, in the city I didnt notice a loss and this is with BFGoodrich All terrains 6 ply

 

i can't wait to get bigger tires and trd rims...just gonna run my rubber till it wears. thanks for the info....good shit

 

You drive downhill both ways? Because your lifted truck is better than stock lol.

 

I lost approximately 1-2 mpg after calculating for size difference. Went from 265/70-16 to 265/75-16. I really notice a difference when I do more 'city' type driving.