I just got a loaner from the dealer for a 09 FWD TL (2336 miles on the meter) & so far I've about 40 miles on it & it's showing 26.5 MPG, very impressive in the hilly roads on HWY 680 here ....

 

On a 300 mile pure highway drive, I got 25 mpg. Pretty darn good for a powerful V6 IMHO.

 

I'm getting 24-25 MPG doing mostly highway driving at 65-70 MPH. I drive the '09 TL FWD.

 

09 TL FWD Tech
90 mile per day round trip commute @ 5000' with 3 1+ mile 7% grades.

Averaging pen and paper 26.1 mpg using Chevron Super Unleaded same station same pump every fill.

Cannot complain given it is not a flat drive, is at altitude and with several mileage busting hills

 

From the dealership, 27.8 MPG on mostly highway at 60-65.

 

My MPG seems to start falling off when I start creeping towards 75 MPH speeds and higher.