[Jackpine]

Dave, the Gryphon's AVG Econ is based on samples of the Inst Econ every second. It is the average of those readings up to a total of 100,000 readings using this formula: ((Current Average * Sample Count) + Current MPG) / (Sample Count + 1)

Once the count reaches 100,000, it no longer changes, so you can see that a new Inst Econ value will have very little effect. But if you reset to "zero", each Inst Econ value will have a much bigger effect. 100,000 samples is about four tankfuls of gas, so this is a pretty large sample space and it covers a lot of different driving conditions.

Still, I find the Gryphon's values to be "optimistic" compared to what I get using a "hand calculation" at fillup.

As far as the tow tune characteristics go, I have not seen what you describe. If I have the speed control engaged when towing, then yes, I get engine braking when going downhill (the Torque Converter tends to stay locked more). But, if I have the speed control disengaged, the TC will unlock almost as soon as I let off on the gas (and Bill said it's supposed to work this way for fuel economy).

In the NEW trucks, I understand when you put them into "Tow Mode" (something new) they provide engine braking going downhill.

I absolutely want engine braking when going down mountain slopes, whether I'm towing or not. I'll put my truck into 2nd gear to give me this if needed.

Hope this makes sense.

- Jack