We Are Being Suckered By Miles Per Gallon Ratings
This is a guest article by Wallace Thomas, an NMA member.
Miles per gallon seems like it’s easy enough to understand, but it’s not. Let give you a hypothetical situation:
Let’s say that my wife and I have two vehicles, the first, is one of those high performance 4wd SUVs that goes like stink, can tow my trailers, but the way we use it, it’s averaging 10 MPG per year of use. The second is a pretty cool sports car. It’s real fun to drive, handles well, and the way we use it, it’s averaging 25 MPG per year of use.
Now, just to make my point, we’ll say that both cost about the same. Both are driven the same amount of miles per year — we’ll say 15,000, and both are the same year — 2005. Now, we realized that replacing two cars at the same time gets quite expensive, so since they both are now 4 years old, we’ve decided we’ll replace one now, the other in 4 more years. This way, we can cycle through, getting one new vehicle every 4 years, keeping each for 8 years and 120,000 miles.
So now we’re looking at two vehicles to decide which to replace.
The proposed replacement for the SUV is an extended cab pick-up. We still need the ability to tow (what with the waverunners, the Harley — there a joke hidden here — and the camping trailer), still need passenger room, but are considering a little more utility, and a little less sport.
The pick-up we’re looking at, with the way we use it, would average 12.5 MPG for a year of use. That’s a whole 2.5 MPG improvement. Woo-hoo.
The sports car replacement would be a sports coupe. Seating for 4, still fun to drive, and the way we use it, it would return around 33.3 MPG for a year of use. That’s an 8.3 MPG improvement — over an already decent MPG. Pretty good, huh?
So, which one will save us more money in fuel?
Well, with a 2.5 MPH improvement versus an 8.3 MPG improvement, it pretty obvious. So the SUV goes, and in comes the pick-up with it’s 12.5 MPG. Huh? What about the 5.8 MPG better we would do with the Coupe? That’s the big problem.
In Europe, they use a different rating system. It’s Liters used per 100 Kilometers. What if we converted to Gallons used per 100 miles? We could call it GPHM (Gallons Per Hundred Miles!)
So here’s the story. The old SUV at 10 MPG is using 10 GPHM. The new pickup, at 12.5 MPG is using 8 GPHM, an improvement of two gallons for every 100 miles driven. In 15,000 miles of use per year, that’s 300 gallons not purchased.
The old sports car used 25 MPG. That’s 4 GPHM. The new one, at 33.33 MPG is using 3 GPHM. an improvement of one gallon for every 100 miles driven. In 15,000 miles of use per year, that 150 gallons not purchased. An improvement of 8.3 MPG saved one half the money and fuel that the improvement of only 2.5 MPG did!
But people don’t think that way. They see the bigger MPG improvement and assume they’ll save more money.
To get the same fuel savings as the truck, the sports car would have to be replaced with a car that gets 50 MPG throughout the year! How many sporty coupes are there around that do that? Now consider this: If you already were getting 33.33 MPG, you would need to get 100 MPG to get the same fuel saving!
So, what I’m putting out there for your mull around is that we should SERIOUSLY look at how we measure and compare fuel use.
I’m including a very simple chart to compare MPG to GPHM. Look and see, if you were to change from a 10 MPG vehicle to a 20 MPG vehicle, you would save more fuel – and money (5 GPHM savings) than switching from a 20 MPG vehicle to a 100 MPG vehicle (4 GPHM savings)! As I said in the beginning, we’re being suckered by miles per gallon ratings.
10 mpg = 10 GPHM
11.11 mpg = 9 GPHM
12.5 mpg = 8 GPHM
14.28 mpg = 7 GPHM
16.66 mpg = 6 GPHM
20 mpg = 5 GPHM
25 mpg = 4 GPHM
33.33 mpg = 3 GPHM
50 mpg = 2 GPHM
100 MPG = 1 GPHM
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I would really like to see the EPA-OBD II Annual Vehicle Emissions Inspection Law closely examined, and changed.As it stands right now, it is entirely possible for any Gasoline powered Vehicle, from 1996 to the present, to fail it’s Emissions Inspection, for not emitting enough Polluting Exhaust Emissions ! All such Vehicles have on board Oxygen [O2] Exhaust Sensors.These O2 Sensors are set up to detect a level of Polluting Exhaust Emissions that would indicate that Gasoline is being consumed by an Engine at 14.7 parts of Air to 1 part of Fuel.If there is a low level of Oxygen, and a high level of Pollution, a Vehicle will fail it’s Emissions Inspection, as well it should.But, Gasoline can be safely vaporized into a mixture that is 100 parts of Air to 1 part of Fuel.With this, even the largest SUV could easily get 50 + MPG, and emit a fraction of the Emissions of a conventional 14.7/1 Fuel System, with an increase in Power, and much longer Engine life.I’m not the first to figure this out.Far from it ! For proof, do a search on [the late] Tom Ogle, and Charles Nelson Pogue.Then, go to http://energy21.freeservers.com/bookrep.html .But, even if it is not to be believed that Fuel Vaporization is entirely possible, it’s illegal to even attempt to do, with any Vehicle, 13 years old, or newer.O2 Sensors are set up to detect that Fuel is being consumed at 14.7/1. A mixture of 100 / 1 will not emit enough Polluting Exhaust Emissions to register on O2 Sensors.When such a Vehicle is connected to an OBD II Emissions Inspection Analyzer, an O2 Sensor Failure Code will be generated, which will result in a failed Emissions Inspection.O2 Sensor Exemptions are permitted for Vehicles that have been legally converted to operate on Natural Gas, Propane, or Hydrogen, and are Registered as such.But not for Vaporized Gasoline.Thus, it is entirely possible, under this EPA-OBD II Vehicle Emissions Inspection Law, for any Gasoline Powered Vehicle, 13 years old, or newer, to fail it’s Emissions Test, for not emitting enough Polluting Exhaust Emissions ! As long as this insane 14.7/1 Law, that only benefits Big Oil, remains in effect, the only way to make Vehicles more “Efficient” will be to make them lighter, and smaller.This has got to change ! I have asked the Question many times ; “Why is it illegal for any Gasoline powered Vehicle, 13 Years old, or newer, to emit too little Polluting Exhaust Emissions”? So far, not one Big Oil Executive, Politician, or Concerned Environmentalist will answer the Question.Those that have replied can’t seem to come up with an Answer.Can you ?
Take a look at this site:
http://www.mpgillusion.com
Or the calculator here:
http://www.gpmcalculator.com
for more on the same idea.
Get a Audi Allroad 4.2L 6spd and call it a day.
That’s true Jeff, but he is saying he needs a truck, and a car not one, or the other.
So is it better to replace the car, or the truck, and by his calculations his truck is a better replacement.
If this article was about replacing both with one, or just keeping one of the vehicles then yes 25/33.33 mpg is the best.
The sports car is already getting better mileage from the start (25 vs. 10mpg). There is no confusion with the current system. 25mpg will save you more money than either 10 or 12.5mpg.