Just added a set of Cooper 315/75 STT's last friday. Here's a by the numbers review.
67 - approximate weight of the tire (stock =56, Toyo 315 =76) one of the deciding factors Cooper > Toyo
34.47 - tire diameter / 11.92 width (vs 35.9/12.9 for toyo 315's - I was looking for a "small" 35 - again another deciding factor)
92.2 - miles indicated vs 100 actual miles traveled - calibration for factory 32's - checked this over two separate 100 mile intervals
1.084 - calibration factor for mileage vs factory 32's based on above actual miles traveled (40 psi)
15.99, 16.33, 16.45 - first three tanks of gas corrected MPG average, mostly highway miles. These trips would normally net at least 17.5 with the 33's
960 - dollars for 4/mb - on the high end of all of the pricing I have heard. Tire was 209 + tax + fees + mb / ea
825 - dollars additional gas cost over standard tires over 50,000 miles @ 10% MPG reduction and $2.75 gas (about 12-14 months for me
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