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Just a follow up on the whole MPG thing.

So lets start off with a pretty straight forward question. Assuming that we are only talking about cost of putting fuel in the car, and not the cost of the car or replacing batteries in a few years etc. Which car swap will save you more at the pump:


1) Getting rid of your 15 mpg truck and trading it in for a mid size sedan that gets 23 mpg (8 mpg better thats a 53% economy increase)

or

2) Trading in your mid size sedan that gets 23 mpg and getting a hybrid that gets 50 mpg (27 mpg better thats a 117% economy increase)




The answer may surprise you, it is number one. Which is why its more important to get out of a real gas hog, and into something reasonable, than to go spend thousands more to get a few MPG. The reason this math works like this is because as you get better millage it scales with diminishing returns the higher you go. Sometimes math is a funny thing, and we humans often get things wrong when we just make a quick mental judgement without actually doing the math. I've given the following talk a few times, and it amazes me how our minds just don't see the truth...and even after I explain it, a good number of people still think I'm doing the math wrong. The bottom line is that in the end, given todays typical fuel economy numbers, any vehicle that gets 30+ is great, your not saving yourself a lot of money trying to get a few mpg more just doesn't normally pay for itself.


THE MATH:::

assuming 250 mile commute and gas at $3.50/gal

Truck 15 MPG will cost $70/week in gas

Sedan 23 MPG will cost $45/week in gas (saving $25/week vs Truck)

Hybrid 50 MPG will cost $21/week in gas (saving $24/week vs Sedan)

Also please note that in the real word your not likely to average 50mpg in the hybrid, but 23 is very realistic for a sedan
 

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yep. diminishing returns as mpg goes up. once we are up arounf 40 mpg's, 5 mpg's more or less dont mean a heck of a lot. thats why i dont want to see hybrid technology used for the sake of a few more mpg's...no point to it.

i will be the first to admit ive become too obsessive about those few mpgs. staying above that 40 mpg mark is a psychological thing. i can recall partaking in many threads about (for example) a 41 mpg cat vs a 39 mpg car. doing the actual math proves how silly it is to have such discussions.

now, discussing 40 mpg's vs something that gets 90 mpg or uses no gas at all is a more worthwhile endeavor.

ive been working on accepting those few mpg's arent worth the worry.
 

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Makes sense.. Then factor in how long at the difference in price it will take you to get that $3,000 - $5,000 more you spent for the Hybrid if the hybrid even gets 50MPG... Just saying...

Not saying Hybrids are bad but I believe they are way over hyped, the real misers of the world are good diesels ( though they currently come with about a $1500 bump) or electric, though electric cars are about $15,000 more than comparable cars (NOT including incentives which will not be around forever)
 

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I think a person should drive the car/truck/suv that they like, be it based on size, utility, towing ability, style, or just the fact that they like the vehicle. If you can afford the payments, you can afford the gas.....and insurance, and maintenance, and sat radio, and cable, and cell phone, and.........awe heck, just drive and enjoy. We'll all be worm food someday.
 

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The actual number of miles that you drive, cost of tires, cost of other maintenance, & cost of insurance must also be factored.

I did a nice spreadsheet for my Power Wagon that, with a Hemi and 4.56 gearing, gets 11 mpg if I nurse it. 4 tires run in the neighborhood of $1200 and are fairly soft rubber. 7 quarts of oil per oil change; 7 quarts of differential gear oil @ $10/quart.
It's an expensive truck to own and run.
If I bought a Pop and just drove it to and from work, overall I'd save a bit over $200 a month. And that's keeping the truck and having the additional insurance nut.
 

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Good for you. I always liked the power wagon. I remember hearing something about the unofficial "how's the economy" indicator. They counted the number of 40 to 50 thousand dollar truck and suvs with bald tires.
 

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THE MATH:::

assuming 250 mile commute and gas at $3.50/gal

Truck 15 MPG will cost $70/week in gas

Sedan 23 MPG will cost $45/week in gas (saving $25/week vs Truck)

Hybrid 50 MPG will cost $21/week in gas (saving $24/week vs Sedan)

Also please note that in the real word your not likely to average 50mpg in the hybrid, but 23 is very realistic for a sedan
Great bit here Mike -

Let me throw another wrinkle into your equation! Let's assume here that you use a vehicle for business purposes to the tune of 20,000 miles/year. Taking Mike's initial setup with a couple of modifications:

Assuming 20,000 business miles per year with $3.35/gal gas (regular) and $3.80/gal diesel

SUV 15 MPG will cost $4,466/year in gas

Mid-size wagon 23 MPG will cost $2,913/year in gas (saving $1,553/year vs SUV)

VW Sportwagen TDI 40 MPG will cost $1,900 in diesel (saving $1,013 vs Mid-size wagon)

In this case, you will get a tax deduction on your mileage - last year it was ~.525 cents/mile - for a total deduction of $10,500.

If you're in the 25% tax bracket, this will mean you actually owe $2,625 LESS tax dollars. Using your SUV, you're still paying almost $2,000 for gas, plus all additional maintenance expenses for the privilege of doing business in your SUV. The Mid-size driver is in much better shape, only having to foot ~$300 plus maintenance. IMO, the real winner here is the VW diesel person who actually pockets over $700 to spend on said maintenance.

Just another wrinkle to consider in the Great MPG Debate...
 

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Good for you. I always liked the power wagon. I remember hearing something about the unofficial "how's the economy" indicator. They counted the number of 40 to 50 thousand dollar truck and suvs with bald tires.
:D

Wouldn't be able to go anywhere that I like to go with bald tires...


 

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Interesting assessment of fuel mileage and costs.

If 11 mpg is even remotely acceptable, I'd like to see the price of fuel double. Using a 4000 lb truck at 10% efficiency to move a 200 lb person is .... well, insert automated asterisks here.
 

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If 11 mpg is even remotely acceptable, I'd like to see the price of fuel double. Using a 4000 lb truck at 10% efficiency to move a 200 lb person is .... well, insert automated asterisks here.
Well, the truck weighs about 7000 pounds, pulls a camping trailer over terrain that would make you weep, and I weigh 255 pounds.

Cutesy little cars can't do everything.
Follow me here in your 500...

 

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Just a follow up on the whole MPG thing.

So lets start off with a pretty straight forward question. Assuming that we are only talking about cost of putting fuel in the car, and not the cost of the car or replacing batteries in a few years etc. Which car swap will save you more at the pump:


1) Getting rid of your 15 mpg truck and trading it in for a mid size sedan that gets 23 mpg (8 mpg better thats a 53% economy increase)

or

2) Trading in your mid size sedan that gets 23 mpg and getting a hybrid that gets 50 mpg (27 mpg better thats a 117% economy increase)




The answer may surprise you, it is number one. Which is why its more important to get out of a real gas hog, and into something reasonable, than to go spend thousands more to get a few MPG. The reason this math works like this is because as you get better millage it scales with diminishing returns the higher you go. Sometimes math is a funny thing, and we humans often get things wrong when we just make a quick mental judgement without actually doing the math. I've given the following talk a few times, and it amazes me how our minds just don't see the truth...and even after I explain it, a good number of people still think I'm doing the math wrong. The bottom line is that in the end, given todays typical fuel economy numbers, any vehicle that gets 30+ is great, your not saving yourself a lot of money trying to get a few mpg more just doesn't normally pay for itself.


THE MATH:::

assuming 250 mile commute and gas at $3.50/gal

Truck 15 MPG will cost $70/week in gas

Sedan 23 MPG will cost $45/week in gas (saving $25/week vs Truck)

Hybrid 50 MPG will cost $21/week in gas (saving $24/week vs Sedan)

Also please note that in the real word your not likely to average 50mpg in the hybrid, but 23 is very realistic for a sedan
Do the same exact cost analysis and increase the annual mileage. The results change.


First and foremost you have to have a vehicle that does the job you need it to do. You can't haul big things in anything but a truck. You can't drive a sportscar on a forest service road.

North America doesn't get the most economical vehicles. My brother-in-law in South America has a full-sized pickup truck with a 1.5L turbo-diesel and gets 28 mpg with it (not highway; they don't have any highways there).
 
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