Fuel Mileage Gauge

[Edahall]

I would like to have a fuel mileage gauge that gives fuel mileage instantaneously as well as average.  These are readily available for vehicles with OBDII 1996 and newer but not for our trucks.  Anybody know where I can buy such a device or are there any older vehicles out there that had this built in that could be retrofitted into our trucks?

[zieg85]

Nothing that I remember.  The only "gauge" was a vacuum "Economy" gauge in old Pontiac cars from the 60's that were under dash mounted as I recall.  I think I have one out in the shed.

[Edahall]

FYI,
I did some looking up and during the 80's before the days of computer controlled cars, there was a unit made by Zemco that did exactly as I described.  It consisted of a main display, fuel flow meter and speedometer.  Based on the inputs, it was able to come up with average fuel economy as well as instant fuel economy.  Unfortunately, these units are quite rare these days.  But it would sure be nice to have this and be able to adjust driving habits to attain the best fuel economy.

Here's a picture of what it looked like.

[zieg85]

Drive like there is an egg between the bottom of your foot and the go pedal.