Today I experienced similar concerns with my 07. First I thought it was the wind so I stopped and checked....no wind....then I figured maybe the winter fuel....jury is out on that one.

I checked my fuel economy as it was just seeming to need to downshift in places it has not done so before. The indicator was showing me about 1.5 mpg under what I normally get on this stretch of highway.

So, I like you are puzzled by this sudden change in performance. It almost felt like there was a drag on the brakes or something, but no dash lights or alignment issues (I did put a lift in about a month ago).

I looked through the TSB's and there was one for sluggish performance I think, but it related to the transmission shift issues which mine doesn't seem to have trouble with.

I also remember a post a while back where someone had this problem, got their ECM flashed and saw both power and MPG improvement. I was quite happy with my 07's perfromance up until yesterday, so will be looking further to see what is going on.