Against 146 other V8 cars rated 1989–1991, the 420 sits right on their 15.2 mpg average.
Every Mercedes-Benz 420 engine, compared
The Mercedes-Benz 420 was rated in a single specification, so its gas mileage does not vary by version — only by model year. Yearly cost assumes 12,000 miles at $3.20 a gallon.
| Engine | Combined | City / Highway | Years | Fuel per year |
|---|---|---|---|---|
| 4.2L 8-cyl | 14 / 17 | 1986–1991 | $2,560 |
What that actually costs
| Measure | Value |
|---|---|
| Cost per mile (1991) | $0.213 |
| Fuel per year | $2,560 |
| Fuel over five years | $12,800 |
| Against other V8 cars, 1989–1991 | +$34 a year |
| EPA's own estimate | $5,150 a year |
City or highway — who is this car for
The 1991 Mercedes-Benz 420 gives up 3 mpg in town: 17 on the highway against 14 in the city, $484 a year if every mile were city driving.
| Measure | Value | Reading |
|---|---|---|
| City (1991) | 14 mpg | $2,743 a year if you only drive in town |
| Highway | 17 mpg | $2,259 a year if you mostly commute |
| Gap | +3 mpg (21%) | Typical for its type |
How the 420 changed over the years
Combined figure across the 6 model years the 420 was rated in, all of them at 15 mpg.
| Model year | Combined | City / Highway | Engines offered | Fuel per year |
|---|---|---|---|---|
| 1991 | 14 / 17 | 1 | $2,560 | |
| 1990 | 14 / 17 | 1 | $2,560 | |
| 1989 | 14 / 17 | 1 | $2,560 | |
| 1988 | 14 / 17 | 1 | $2,560 | |
| 1987 | 14 / 17 | 1 | $2,560 | |
| 1986 | 14 / 17 | 1 | $2,560 |
MPG is a number. Dollars per year is the answer.
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How we count
This page rests on 6 EPA ratings of the Mercedes-Benz 420 — 1 engine across 1986–1991. The mileage is EPA's laboratory figure, unchanged; the yearly bill is ours, at 12,000 miles and $3.20 a gallon, against EPA's own estimate of $5,150. Full method.
Frequently asked questions
What mpg does the 1991 Mercedes-Benz 420 get?
15 mpg combined, 14 city and 17 highway, per EPA. Across every year since 1986 the 420 has averaged 15 mpg.
Is the 1991 420 more efficient than the 1990?
About the same: 15 against 15 mpg combined.
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