3790LMT ECO question?

The higher the number, the higher your mileage, and eco-friendliness is. Braking, acceleration, and a steady speed are included.

Don't have an accident while you stare at this thing

the numbers it displays while you are at a steady-state speed are based on the city and highway mileage per gallon vehicles numbers currently set on the device. Can get to the screens for putting those numbers in from the ecoroute item on the menu.

I happen to have taken careful data on my Audi A4 for the relationship of fuel economy versus steady-state speed, and can say with some assurance that the numbers the Garmin displays bear a rather distant relationship to the truth. for example: in 5th gear my A4 gets steadily worse mileage as speed increases above the minimum of 30 mph. However with the city and highway mileage numbers set to those that Audi measured by EPA means for the car, 3790 LMT suggests a broad flat spot of optimum economy in the range of about 50 to 60 mph--which is what a lot of people believe, but is not true.

Here is a graph of data I carefully logged on my A4 with repeated bidirectional trials on the same piece of road at the same temperature with a throughly warmed-up engine.

http://i6.photobucket.com/albums/y231/PeterAStoll/problems/a...

Yes--I do understand that the 3790 display is of "goodness", not directly mpg--but it does not show maximum goodness anywhere near the right speed.

I got tired of looging in gas usage and mileage. Then for whatever reasn it seemed that steady state didn't work. The faster I went, the better the number.

Thank you for the explanations, much appreciated.

I am not yet where pwohlrab is, I enter my numbers faithfully in the Garmin as well as in a SCANGAUGE II which gives me a lot more info than the 3790.

Well you know how it is, men and their toys!