Allison Economy Mode

[pp3harris]

When the red indicator light is "on" after the Economy mode button is pressed, is that indicating that the economy mode is engaged or is it warning you that the economy mode is NOT engaged. I once asked an Allison service rep that question and he said to not worry about it, that a lot of RV manufacturers didn't even bother to hook it up and that the light actually wasn't indicating anything. I never bother with it. I run with the light "off" all the time. CAT 3126, Allison 3060, Holiday Rambler Endeavor, towing a Geo Tracker, I get 8-9 MPG.
I have just been reading posts about the economy mode and I was wondering what I was missing.
Thanks for the input

 

[docj]

My guess is that the light is on when you are in Economy Mode, but my honest opinion is that it doesn't make all that much difference anyway.  Economy mode changes the shift points a bit so on rolling terrain you don't downshift as easily into 5th.  It has absolutely no effect on level terrain driving like you find on most interstates.  My rig won't shift into 6th until ~62 anyway, so with rolling hills on 2-lane roads I'm probably not in 6th anyway so the switch to Economy has no effect.

With the mileage you are reporting I don't think you're going to see much difference between the two settings, although I'm sure someone will post that driving in Economy mode forces the engine to lug closer to its max torque point which is the more efficient way to drive a diesel.  My answer to that is that if I'm not really going to see any mileage difference I'd rather run in the lower gear at slightly higher revs to get the better engine responsiveness.

 

[Alaskansnowbirds]

When the light is ON the transmission is in economy mode.

As Joel said, it just moves the shift points. The MH we had had the same engine and trans. I could definitely see the difference when pulling a hill by watching the tach. With it in economy it would go down about 500rpm further before downshifting than if I wasn't in economy.

When pulling a hill I found if it wasn't steep enough to keep it in 5th or a lower gear my MH would hunt between 5th and 6th if it wasn't in economy and they were hard shifts. In economy mode, when it did downshift, it was very smooth. But I think that was a problem in the transmission programing and didn't have anything to do with the economy mode being on or off.