285 vs 265 vs MPG
Moderator: volvite
285 vs 265 vs MPG
Hello everyone. I am very close to purchasing a new Pathfinder this weekend. I have been reading the posts and would like to install a 2 " lift as soon I get the car. I'm debating if I want to go 285/75/16 or 265/75/16. I have decided on General Grabber AT 2's. Does the 1" larger tire really make that big of an impact on mileage? They do seem to fill out the wheel well better..... thanks in advance!
Kind of a double whammy since you're also adding 20mm of width.
I've got a commuter vehicle so to speak, so I really didn't buy the Pathy for MPG's, but I would stay smaller if in fact it is your DD.
Shouldn't look that bad even with 2" of lift and finding a happy medium in tire size.
These in the picture are 31.5" w/ 2.5" lift, which is right about where the 265/75-16's you were thinking of. Although the pictured are 18's, overall dia. is the same
I've got a commuter vehicle so to speak, so I really didn't buy the Pathy for MPG's, but I would stay smaller if in fact it is your DD.
Shouldn't look that bad even with 2" of lift and finding a happy medium in tire size.
These in the picture are 31.5" w/ 2.5" lift, which is right about where the 265/75-16's you were thinking of. Although the pictured are 18's, overall dia. is the same
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RacerZX
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So...it's bad, but not necessarily as bad as it seems.
Yes, the taller tire raises the body increasing frontal area and aerodynamic drag, and a wider tire both increases drag from road friction AND increases the frontal area.
But, it's not all bad. A taller tire also increases the tire's circumference, which makes the engine's gearing taller, slowing your acceleration and giving you lower engine RPMs at the same speed which is a good thing for MPG.
However, you never really see that benefit unless you do careful math and testing, because now both your speedometer and odometer are wrong. What was 69MPH is maybe now 73MPH, and what was 1 mile is now 1.07 miles. That means your truck is doing more real work by going faster and further than your MPG display is telling you.
I had fun testing this one out after putting the big 285s on my truck. Doing before and after testing, using GPS to make sure I was driving at the same real speed, and to correct the odometer distance, I found that after the upgrade my real MPG was about 10% higher than the computer. So 15MPG is really 16.5MPG.
Food for thought...and as always, YMMV
Yes, the taller tire raises the body increasing frontal area and aerodynamic drag, and a wider tire both increases drag from road friction AND increases the frontal area.
But, it's not all bad. A taller tire also increases the tire's circumference, which makes the engine's gearing taller, slowing your acceleration and giving you lower engine RPMs at the same speed which is a good thing for MPG.
However, you never really see that benefit unless you do careful math and testing, because now both your speedometer and odometer are wrong. What was 69MPH is maybe now 73MPH, and what was 1 mile is now 1.07 miles. That means your truck is doing more real work by going faster and further than your MPG display is telling you.
I had fun testing this one out after putting the big 285s on my truck. Doing before and after testing, using GPS to make sure I was driving at the same real speed, and to correct the odometer distance, I found that after the upgrade my real MPG was about 10% higher than the computer. So 15MPG is really 16.5MPG.
Food for thought...and as always, YMMV
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