What Is a Good MPG?
“Good MPG” depends on the vehicle. A compact car around 30–40 MPG combined is strong; a full-size truck in the high teens to low 20s is normal. What matters most is the gap between your current MPG and a replacement, multiplied by your annual miles.
For reference, EPA combined ratings in the US typically run: subcompact ~30–37, midsize sedan ~28–35, small SUV ~25–31, full-size truck ~17–23, and many hybrids ~40–55. These are lab estimates; real-world results vary with conditions.