Graded within its segment: why a truck's MPG is not a sedan's
Every measured spec is normalized against a band for the vehicle's own body type. What the bands are, how a value turns into a score, and why the same number grades differently in different classes.
A pickup that returns 24 MPG combined is a frugal pickup. A sedan that returns 24 MPG is a thirsty one. If both were scored against a single fuel-economy band the truck would fail and every sedan would look average, and neither result would help anyone choosing between two trucks. So every measured criterion on MotorGPA is normalized within the vehicle’s own segment — one band per body type — and the grade answers the question “how good is this, for what it is?”
Nine segments, one band each
The segment is the registry’s body-type category: truck, SUV, sedan, minivan, hatchback, coupe, convertible, wagon or van. Each measured criterion carries a band — a minimum and a maximum — for every segment it applies to, and a value is scored as its position between the two. The bands are published, and they are meant to be argued with: a band is a claim about what the real range of the class is.
| Segment | Band (MPG) | Score for 24 MPG |
|---|---|---|
| Trucks | 14–27 | 77 |
| SUVs | 16–33 | 47 |
| Sedans | 18–42 | 25 |
| Minivans | 16–33 | 47 |
| Hatchbacks | 18–42 | 25 |
| Coupes | 18–42 | 25 |
| Convertibles | 18–42 | 25 |
| Wagons | 18–42 | 25 |
| Vans | 12–24 | 100 |
The table above uses the gas band. Fuel economy is also split by powertrain class, which is its own rule and its own guide: Efficiency is graded within powertrain class.
The same rule everywhere a number is scored
Cargo volume is the clearest case, because the segments are not even measuring the same thing. A sedan’s trunk and an SUV’s cargo area behind the second row are both “cargo volume” in cubic feet, and one is routinely three times the other. A single band would give every sedan a zero.
| Segment | Band (cu ft) | Score for 15 cu ft |
|---|---|---|
| SUVs | 25–80 | 0 |
| Sedans | 10–20 | 50 |
| Minivans | 50–105 | 0 |
| Hatchbacks | 8–28 | 35 |
| Coupes | 4–26 | 50 |
| Convertibles | 4–14 | 100 |
| Wagons | 10–20 | 50 |
| Vans | 50–480 | 0 |
It applies to inverted criteria too. Turning circle is scored lower-is-better, and a 40 ft circle — ordinary for a mid-size SUV — scores 100 against the truck band of 40–54 ft and 0 against the sedan band of 34–40 ft. A truck that turns like an SUV is remarkable; a sedan that turns like an SUV is not.
Criteria that do not apply
Some measurements only exist for some body types, and the framework handles that by omission rather than by a zero. Bed length and payload are truck criteria; towing capacity applies to trucks, SUVs, minivans and vans; third-row usability to SUVs, minivans and vans. A sedan simply does not carry those criteria, and the weights of the criteria it does carry are renormalized so its category score is still an average over what was measured. A two-seat roadster likewise drops the rear-seat criteria — rear headroom, rear legroom, child-seat usability — because it has no rear seat to measure, and the framework gates those on seating capacity rather than on body type, since a four-seat convertible does have one.
| Body type | Models | Median towing | Median score |
|---|---|---|---|
| Vans | 4 | 6,850 lb | 83.5 |
| Trucks | 22 | 9,645 lb | 64 |
| SUVs | 160 | 3,500 lb | 36 |
| Minivans | 5 | 3,500 lb | 36 |
What this means for reading a grade
A grade on MotorGPA is comparable within a body type and only loosely across them. An A in Comfort on a compact hatchback means “among the most comfortable compact hatchbacks”, not “as comfortable as a full-size luxury sedan with an A”. That is a feature — it is the comparison a shopper is actually making — but it is also why the honor roll awards subjects per segment and why the segment is printed beside every grade. The one place cross-segment comparison is fair is on the raw values themselves, which is what the compare tool is for.