70 mpg at around midnight till dawn

I've been successful multiplying the mpg reading by 10 and filling up when the miles/tank reaches that product but this only works if you start with a completely full tank which, in cold weather, isn't always achieved. Someone here (Michelle?) mentioned running out of gas using this technique.

"Bill" wrote in message news:9PSdnQMkOcJgOifZnZ2dnUVZ snipped-for-privacy@onvoy.com...

As the weather turns colder capacity shrinks. It's due to contraction. The incoming gasoline's temperature is consistent within a few degrees. During the warm summer months the gasoline is cooler than what's in the tank already. But in the winter the gasoline is warmer than the what's in the tank already. The bladder will expand as much as it can within the confines of the metal tank. The metal tank is smaller in the colder climate. There's a certain terminology home delivery oil dealers use but it escapes me at the moment. It's a consideration they have to take into account when assessing the capacity difference of their delivery trucks when it's winter and when it's summer. Buying home heating oil in the summer may not be such a good deal after all. $2.19 per gallon during the summer could translate to $2.59 during a winter delivery and it's not necessarily greed but increased density. I used to machine steel plugs so the outside diameter was .0001" plus or minus 50 millionths of an inch, larger than the inside diameter of the metal cylinder it was going to be inserted into. It's called a press fit only because no epoxy is used to keep them together. The plug is shrunk by using cold and it easily slips inside. The end of the plug had a tolerance too as far as how much recessed or how much it could protrude from the cylinder. Too much or too little and it was too late. The whole combined part could not be machined to be within spec nor could the two parts be separated by cold or heat. The outside of the cylinder had a well defined micro-finish. It couldn't be held in a conventional chuck and it was too small to withstand surface grinding and held in place by electromagnetic means. There's also other special ways to grasp for machining but I'm not obliged to say.

That's right, but that's because I didn't take into account the special circumstances--namely that I would be climbing the Grapevine on I-5; mileage going up such a steep hill is much lower than it would be on level ground.