i knew when i put my winter tires on my speedo would be off... well following a freind the other night he was doing 75 and i was doin 80.... did that test again following a different vehicle and the same result..

im calibrated for 275's but my winter tires are 265's and havnt got my hypertech yet

so im 5 mph above the norm

so if ive been getting 260-270 miles to the tank..26 gallon tank... what would that be in actuall numbers?

i cant figure out the math for the life of me..

 

Ummmm that's like 10 miles to the gallon....not good...

However, I'm assuming that you are wanting to know if going 5mph over it affecting your mpg? I dont know that 5mph would make/break you by a whole lot on the gas consumption..

 

yea i know i get super crappy gas mileage... not sure why...got a dual exhaust and a CAI... but then again i didnt get a dodge ram 5.9L to save mother earth

 

running smaller tires than what you are calibrated for will also make your truck log more miles on the odometer than it is actually traveling. I am experiencing this with mine, its set for 315's and i have 265's on from the dealer. every 100 miles i travel, it puts 110 on the odometer. yours wont be so drastic, but it will still add up over time.

 

yea ive put on 3000 miles with these smaller tires... i knew that it would be off some what...

i think im gonna have to tackle this crappy gas milage... 10mpg highway is unacseptable regardless what kind of vehicle it is.. even with a cai and a dual exhaust (headers and a highflow cat)