During the warm months my Cobalt is accomplishing what seems unreal mpg's. Traveling at 55 mph with the cruise control on, on a simi flat road the trip computer reports 50 mpg. I believe I get better than that though, I traveled about 115 miles on an 1/8 tank of gas. Im not sure how many gallons an 1/8 tank is? Its an 06 ls sedan 2.2L ecotech 5-speed, I try to keep the rpms under 2k when accelerating. I guess, Im just wonder if any else gets mgs like this in their Cobalt?

 

are you running synthetics, is your car stock or have you modded anything?

in warm weather I run about 36MPG - 38MPG.

it could be a combo of variables, I mean its possible... but extremely rare

 

I want a Cobalt simply for that reason. My ex-girlfriend had one and liked it.

 

No and no its completely stock, going on 80k miles. Its only on my way to work I get excellent milage. I stop only 3 times, no traffic lights and 1 stop sign. The road is level almost all the way. When approaching towns I leave it in 5th for speeds down to 30 mph. Ive been using an 1/8 tank on my round trip of about 115-120 miles. Driving with lots of stops, or short trips I get 38-40 mpg. In the winter its gotten as low as 26. Is your car manual?and whats your driving style?

 

I guess its possible. I have seen reports of those new AFM Tahoes getting about 26 MPG highway.
Do you practice "hypermiling"?

 

You can go to the extreme with hypermiling. Since you have the manual, you can bring it up to speed then put it into neutral and kill the car (do not lock the steering wheel). After it goes down to a certain speed, you can crank it back up (with starter or using clutch) and slowly get back up to speed and do that again and again. When i had my blazer, i did that, except I had an automatic so I didn't kill the engine, I just put it in neutral and coasted. I got 28 mpg one time doing that. I normally got 21-23 so I gained a pretty good bit. My dad did it in a 5-speed camry and got 45 when it usually got 32. Of course, coasting is illegal (or at least it is in Texas) but what they don't know won't hurt them.