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with the new tires.
Stock tires were P225/75 R16 = 29.6 diameter
New tires are LT265/75 R16 = 31.8 diameter
That equates to a 8.1% difference.
Any examples would be great.
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quote:You speedometer will be far enough off that you should be thinking about it when you are might be around traffic cops. Multiply 1.0743 times your speedometer reading, like 65 speedomoter x 1.0743 = 69.8 which is basically 70. If you just add 5 mph at highway speed and 2 mph at city street speeds you won't be far off of your old readings.
Originally posted by Ramblin Fever: So, basically before yesterday's fill-up, I logged 202 miles (I fill up at the half-way mark) - can I just do 202 x 7.43% = 15.0086 So, actual mileage would be 202 + 15.0086 = actual mileage?? Thank you!
quote:Looks like everyone missed the actual question! Yes, that's the way to do it.
Originally posted by Ramblin Fever: So, basically before yesterday's fill-up, I logged 202 miles (I fill up at the half-way mark) - can I just do 202 x 7.43% = 15.0086 So, actual mileage would be 202 + 15.0086 = actual mileage??
quote:Looks like everyone missed the actual question! Yes, that's the way to do it.
Originally posted by rpn453:
quote:Yep, that is correct. More than likely you'll note a drop in mileage with that big of a jump in tire size, and also with the change to an LT tire. The larger diameter doesn't offset all the extra weight the bigger heavier tire brings along with it.
Originally posted by rpn453:quote:Looks like everyone missed the actual question! Yes, that's the way to do it.
Originally posted by Ramblin Fever: So, basically before yesterday's fill-up, I logged 202 miles (I fill up at the half-way mark) - can I just do 202 x 7.43% = 15.0086 So, actual mileage would be 202 + 15.0086 = actual mileage??![]()
quote:Don't worry about wear because of tire weight. You have gained 48 lbs of tire, which worst case would be about the equivalant of 100 lb weight in the truck. About like picking up a real skinny girl. Unsprung tire weight adding the equivilant of 8 times unspring weight is just unfounded urban (maybe rural) legend.
Originally posted by Ramblin Fever: Actually I got a 2 mpg increase this week; however, I'm seriously thinking about going to the 265/70's instead. BigOTire & Yokohama give you free 30 day test drive. I love the height of these 75's, however they weigh 50# each versus 38# of the 70's. More leary of wear/tear on the transmission although there are LOTS of people running the 75's on the 3.2L V6.
quote:This isn't surprising. Because as Racer put it,
Actually I got a 2 mpg increase this week; however, I'm seriously thinking about going to the 265/70's instead.
quote:Thus you are turning lower RPMs than before at the same speed. This can result in a MPG increase, of course this depends on many factors such as the additional load placed on your engine as it now has to operate in a lower RPM range than was intended. Sometimes this can offset any MPG increase gained from lower gearing.
with a taller tire you are numerically lowering you effective gearing which puts a little more strain on the trans.