I am happy to report getting 37 mpg low grade driving no serious uphills and 36 mpg cross country driving all while driving conservatively at 65mph. 2010 2.4L ecotec 6 speed automatic. All this after I started to noticed lost in mpg, serviced injectors 2 were clogged due to carbon/oil in intake/ runners all cleaned up. Installed a home Depot catch can to prevent it from happening again at the pvc line. Bought it used a few months ago is the best I've seen this car raned.
Good lord, I'm doing something wrong here - I'm consistently between 19-20 mpg. Since I work from home, the majority of my travel is suburban (~35mph average), but even when I do have a lot of highway driving, I never get any more than 270 miles out of a tank before a refill.
Granted, I'm in a heavier 'vert, but should it be quite this low?
2008 vert, 3.5 engine, 4-speed auto trans. Around town, much less than 19mpg, can't really compare because traffic is never the same. But at steady 70mph with the top up, level road, no wind, no passengers, no AC, I get very consistently 33mpg according to the display. Fuel measurement shows reading is accurate.
2007 Vert here, another 4 spd 3.5L, but I'm rocking a fairly consistent average of 23.9mpg with combined highway and city travel. I spend about 20 miles on the highway at around 70-80mph, and then something like 15-20 minutes over 10 miles city averaging about 35-40mph. In the hills no less! With solid highway driving, I've averaged as high as 24.8mpg, but I don't do much less than 75-80mph when I drive highway. I typically have the AC on and haven't averaged without it yet, but 400 miles +- 20 on $30 of gas a week isn't something I'm gonna complain about.
Edit: Went to Austin from San Antonio last weekend, somehow managed to average 30mpg, so not too shabby