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New to the forum, and to ford. Just let go of my beloved 2010 4Runner Trail edition for a loaded EB 3.5 SCrew Lariat Sport in Silver. So far so good. First thing that had to go was the stock wheels & tires. Swapped for a set of BMF Novakane 20x9 wrapped in 275/55/20 Nitto Terra Grappler G2s, zero offset. I'll admit i was pretty shocked at just how bad the gas mileage was affected. Went from 22.5 on the interstate, now down to 17H/15C. Hoping this will improve as it continues to break in, But if not then please warn me.
Wondering a couple things. Ford told me an alignment wasn't necessary even though i went from the 18/8.5 wheels at a +44 offset to whats mentioned above. That doesn't seem to sit right with me. Thoughts?
Secondly, should i get the computer recalibrated to reflect the increased wheel size, and if so will that help the computer make a bit more sense of the fuel economy?
I understand this is a heavy truck (despite the weight shedding), but regardless of how sweet the stance is now the gas mileage was affected a bit too much for my brain to comprehend.
For any of you who've made the same change, whats your economy looking like?
Any info would be great. Cheers!
Last edited by Paragon1; 04-13-2015 at 05:45 PM.
Reason: Pica
Wheel size does not matter but you need a new calibration if the overall tire height is different. Welcome to Ford and to this site.
Are you saying wheel size doesnt matter in regards to gas mileage??
Only my 2009 F150 FX4 i went from stock 18s to 20s and my mileage was terrible. I think i was averaging around 13-14 but that was on the older 5.4 as well.
Are you saying wheel size doesnt matter in regards to gas mileage??
Only my 2009 F150 FX4 i went from stock 18s to 20s and my mileage was terrible. I think i was averaging around 13-14 but that was on the older 5.4 as well.
Generally, assuming the total weight of wheels and tires is similar, wheel size does not matter. What matters is the outside diameter of the tires. You could have 15" wheels and 22" wheels both have the same outside diameter wheels. As long as the weight of the wheels/tires combined is the same, MPG won't be affected.
However, if the tires have a diameter that is 10% larger, then fuel economy will go down 10% due to the fact that the odometer is registering 10% fewer miles than actual, though you are using the same amount of fuel to travel that distance.
This doesn't take into account the extra mileage hit you take due to aerodynamics when you raise your truck up in the air an inch for those 2" taller tires. I have also ignored the differences due to the weight being distributed differently on the wheels/tires. Generally, the further from the center of the wheel that the mass is, the less MPG you will see due to the extra energy it takes to spin mass that is further from the center.
Are you saying wheel size doesnt matter in regards to gas mileage?? Only my 2009 F150 FX4 i went from stock 18s to 20s and my mileage was terrible. I think i was averaging around 13-14 but that was on the older 5.4 as well.
No, I'm answering his question. The wheel size does not in itself require a recalibration. It's the diameter if the tires that determines the need.
Generally, assuming the total weight of wheels and tires is similar, wheel size does not matter. What matters is the outside diameter of the tires. You could have 15" wheels and 22" wheels both have the same outside diameter wheels. As long as the weight of the wheels/tires combined is the same, MPG won't be affected.
However, if the tires have a diameter that is 10% larger, then fuel economy will go down 10% due to the fact that the odometer is registering 10% fewer miles than actual, though you are using the same amount of fuel to travel that distance.
This doesn't take into account the extra mileage hit you take due to aerodynamics when you raise your truck up in the air an inch for those 2" taller tires. I have also ignored the differences due to the weight being distributed differently on the wheels/tires. Generally, the further from the center of the wheel that the mass is, the less MPG you will see due to the extra energy it takes to spin mass that is further from the center.
I assume youre referring to offset in thatast part. If so, are you saying that the torque required to get the mass rotating is less provided the point at which the torque is being applied is centered on the wheel. By that logic it says the +44 offset the factory uses is less efficient than a 0 offset. I'm by no mans a physicist, just looking for clarity. My thoughts are that the weight increased 10% as did the diameter by ~2in. Will be interesting to see how/if the gauges are affected by getting it reprogrammed to account for the bigger wheels and tires.
I assume youre referring to offset in thatast part. If so, are you saying that the torque required to get the mass rotating is less provided the point at which the torque is being applied is centered on the wheel. By that logic it says the +44 offset the factory uses is less efficient than a 0 offset. I'm by no mans a physicist, just looking for clarity. My thoughts are that the weight increased 10% as did the diameter by ~2in. Will be interesting to see how/if the gauges are affected by getting it reprogrammed to account for the bigger wheels and tires.
No, offset has nothing to do with it. The distance I am referring to is the distance from the center of the wheel/hub to the outside edge of the tire. The diameter or height of the tire. The offset is the distance straight along the axle.
04-13-2015, 05:42 PM
