I always forget about the plastics thing. I do my part to keep that going through my soda consumption!

I haven't changed my driving habits since the prices started skyrocketing, and I don't plan on it.

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Dynamite comes in small packages, Nitro comes in smaller ones, take your pick!

Not exactly. You are forgetting about the engine efficiency (which is only about 40% IIRC). At some point the amount of fuel burn is not going to decrease enough with reduced road speed to make a difference. Simply put, there's a speed, at which point going slower does not save fuel. In fact, MPG decrease because the engine is going to burn "X" gallons per hour regardless of the speed. This is why drivers will say they sometimes get better mileage at higher speeds. Even though they are encountering more resistance and friction at a higher speed (lower theoretical MPG), the distance being covered vs. the fuel being burned results in higher "real" MPG ... AKA: the "sweet spot".

Thank you,
To understand this is simple--A computer. There are many vehicles that have multi-sync chips that work with the engine sensors, speed sensors, and transmission sensors. These chips calculate many times a second for optimum fuel effeciency at a targeted speed.
The term, for anyone interested, is refered to as Stoichiometrics. The correct air/fuel ratio needed for an internal engine to perform at maximum effeciency. With the invention of the computer, a thing called a potentiometer(or in vehicles an airflow meter), a BMAP (barometric/manifold absolute pressure) sensor, an oxygen sensor, a speed sensor, a TPS(throttle position sensor), a transmission shift select sensor, computer controlled fuel injectors, an EGR(exhaust gas recirculation) and a few others, the optimum air/fuel ratio can be obtained at the desired speed--or target speed.
The national speed limit is, except for a few states, 70 MPH, with a few at 75 MPH. Since this is common knowledge the auto industry has improved eveything including transmissions to get the best air/fuel ratio at 70 MPH(the sweet spot).
This is one reason auto manufacturers suggest placing auto overdrives in direct drive at reduced speeds or when towing.
The next invention has already been invented. A computer operated 2- speed final drive. The 2-speed final drive is almost as old as trucks but computer assist will make it practical in FWD vehicles. Since smaller vehicles make larger transmissions impractical this will be he next step. Since it has not been printed yet remember I said this first.
I hope I have placed enough information in this posting so it will at least seem that I know what I am talking about. Before retiring I was computer diagnostics technician on GM vehicles then ventured into other vehicles including big trucks. I am a little rusty but not rusted.

Have you tried WD-40?

BTW, I found your post to be quite informative.
Rusty or not.
Thanx.

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Pontificating Dogmatist

Thank you but maybe I should try white lithium. I would like to mention something about the fuel prices. I am amazed with what has been happening over the last year. Fuel prices went through the roof and was helped when the soon to be late(out of office) great Mr. Bush wrote OPEC a blank check. He did this when he went on national TV and stated he would never release our oil reserves to lower fuel prices.
The fact is that the U.S. has a lot of oil. There are some that believe we must have plenty of oil in reserve to fight wars. The U.S. is one of the largest purchasers of oil. As oil reserves are used more is purchased. This in itself causes an increase. When the prices started climbing many said it could not be helped. That oil was traded on the stock market and things just happen. Oil companies reported massive gains and profits. Everyone was saying we would have to do something drastic and we did. We voted in a democrat and the price of oil started dropping. I saw today it was down to $1.54 and may fall lower.
Here is the part I find amusing. The oil that reached outrageous prices just because that was the way it was, world market and all, started getting cheaper. The President of OPEC went on TV and said OPEC would start cutting oil production to stabalize prices. On over night trading it got cheaper. It was alright when it got so high we were spending all available cash and many were doing without to purchase fuel. When it started dropping someone wanted to cut production to keep prices higher. So much for free market.
Sounds like a good conspiracy theory to me. I would like to know, if we are in bad shape and getting worse, why is the Wal-Mart parking lot always full and the hiways crowded? I would like to know some rational theories.