You know. I have a 5.9L 360 gas motor on my 4X4 Dodge, and I am getting 16 city, and about 20 - 22 highway. Now about 40,000 miles ago, i replaced my tranny and did the heads on the motor. I put a cooler thermostat, bigger tranny cooling lines and bigger radiator, due to the fact that these motors like to run really hot. So I decided to try something new, then I had to re-program the computer for the check engine light coming on due to it running too cool for the factory specs programed. It actually smogs better, and runs so much better now. It is all stock however, but the motor has been modified, when we pulled the heads to work on it at my uncle's shop. When we threw it on the Dyno, it has a little over 300 horses or something like that. This was a while ago, I need to check the print out.
