[Shop-talk] 6 to 3 fuel saving

[Steven Trovato]

I'm not accusing anyone here of doing this, but it seems that 
sometimes people misinterpret fuel mileage improvements.  If you're 
getting 10 miles per gallon, and you do something that gives you 11 
miles per gallon, it doesn't sound like much, but it is a 10% improvement.

At 10mpg:

If you drive 10000 miles per year, that's 10000 miles divided by 10 
miles per gallon = 1000 gallons, times $4 per gallon, thats $4000

At 11mpg:

If you drive 10000 miles per year, that's 10000 miles divided by 11 
miles per gallon = 909 gallons, times $4 per gallon, thats $3636

So you saved $364.

At 30 mpg:


If you drive 10000 miles per year, that's 10000 miles divided by 30 
miles per gallon = 333 gallons, times $4 per gallon, thats $1332

At 31 mpg:

If you drive 10000 miles per year, that's 10000 miles divided by 31 
miles per gallon = 323 gallons, times $4 per gallon, thats $1292

So you saved $40.

Bottom line is, one "1mpg" increment is not necessarily equivalent to another.