Originally Posted by ZenFocus
For all of you that had the latest software upgraded and are getting worse mpg, I suspect the tranny have been reprogrammed to upshift later than sooner to smooth out the shudder which means it will hold its gear a little longer before shifting to the next one. This I think will results in poorer mpg due to the engine having to rev somewhat higher to put it in the torque RPM range to eliminate the shudder. I believe the shudder you experienced earlier is due to the DCT upshifting very early to optomize mpg. Unfortunately, your engine will run in each gear in the lower RPM which is outside the engine torque range. I know so due to my experience driving a stick in my younger days. Whenever the shudder happens, I have to downshift. You're lugging the engine when the RPM is lower than the torque range of this 4 cylinder which I think is around 4400 RPM. The tranny upshift around 2500-3000 RPM. I for sure will not have them reflash my tranny as I don't yet have the shudder issue and am getting pretty good mpg. The old saying goes: If it ain't broke, don't FIX it. Would it be interesting if Ford resubmit their focus with the reprogrammed transmission to the EPA for revised mpg rating? I have a feeling they will not as they already know the outcome which will not look pretty.
To improve your mileage and to make the trans shift earlier, lighten up on your right foot. That's the ticket right there.