Infiniti Q45
18 MPG The 2006 Infiniti Q45 is EPA-rated at 18 MPG combined (16 city / 22 highway). Over 15,000 miles a year that is about 833 gallons, $2667 a year in fuel, or $0.178 per mile at $3.20/gal.
Across its full 1990–2006 run it averages 17.6 MPG, improving by 1 MPG over 17 model years.
Running cost at different fuel prices and mileages
The figure everyone actually wants, and the one the EPA does not publish — because it depends on a fuel price no agency will commit to.
| Fuel price | Per mile | 10,000 mi/yr | 15,000 mi/yr | 20,000 mi/yr |
|---|---|---|---|---|
| $2.50/gal | $0.139 | $1389 | $2083 | $2778 |
| $3.00/gal | $0.167 | $1667 | $2500 | $3333 |
| $3.20/gal | $0.178 | $1778 | $2667 | $3556 |
| $3.50/gal | $0.194 | $1944 | $2917 | $3889 |
| $4.00/gal | $0.222 | $2222 | $3333 | $4444 |
| $4.50/gal | $0.250 | $2500 | $3750 | $5000 |
| $5.00/gal | $0.278 | $2778 | $4167 | $5556 |
Every model year
| Year | Combined | City | Highway | EPA fuel cost/yr | CO₂ g/mi | Trims |
|---|---|---|---|---|---|---|
| 2006 | 18 MPG | 16 | 22 | $4300 | 494 | 1 |
| 2005 | 18 MPG | 16 | 22 | $4300 | 494 | 1 |
| 2004 | 18 MPG | 16 | 22 | $4300 | 494 | 1 |
| 2003 | 18 MPG | 16 | 22 | $4300 | 494 | 1 |
| 2002 | 18 MPG | 16 | 23 | $4300 | 494 | 1 |
| 2001 | 18 MPG | 16 | 21 | $4300 | 494 | 1 |
| 2000 | 18 MPG | 16 | 21 | $4300 | 494 | 1 |
| 1999 | 18 MPG | 16 | 22 | $4300 | 494 | 1 |
| 1998 | 18 MPG | 16 | 22 | $4300 | 494 | 1 |
| 1997 | 18 MPG | 16 | 22 | $4300 | 494 | 1 |
| 1996 | 17 MPG | 15 | 20 | $4550 | 523 | 1 |
| 1995 | 17 MPG | 15 | 20 | $4550 | 523 | 1 |
| 1994 | 17 MPG | 15 | 20 | $4550 | 523 | 1 |
| 1993 | 17 MPG | 15 | 20 | $4550 | 523 | 1 |
| 1992 | 17 MPG | 15 | 20 | $4550 | 523 | 1 |
| 1991 | 17 MPG | 15 | 20 | $4550 | 523 | 1 |
| 1990 | 17 MPG | 15 | 20 | $4550 | 523 | 1 |
Where a model year offered several engines or drivetrains, the figure is the average across all EPA-tested trims that year — the trim count is shown so you can see how much averaging is involved.
How it compares in its class
Among the 261 midsize cars models tracked here, the Infiniti Q45 ranks 222 on current figures, against a class average of 27.3 MPG.
Closest more-efficient alternatives in the same class: Audi 100 (18.5), Bentley Flying Spur (19), BMW 550i xDrive (19), BMW M850i xDrive Gran Coupe (19), Buick Riviera (19).
Tailpipe CO₂ is rated at 494 grams per mile, which works out to roughly 7.4 tonnes a year at 15,000 miles.
Questions
What MPG does the Infiniti Q45 get?
The 2006 Infiniti Q45 is rated at 18 MPG combined by the EPA — 16 city and 22 highway. Across all 17 model years in the database it averages 17.6 MPG, ranging from 17 to 18 depending on year and trim.
How much does a Infiniti Q45 cost in fuel per year?
At 18 MPG and 15,000 miles a year, it burns about 833 gallons — roughly $2667 a year with fuel at $3.20 a gallon, or $0.178 per mile. The EPA's own published annual figure for the 2006 model is $4300.
Has the Infiniti Q45 become more efficient over time?
Yes. It has gone from 17 MPG in 1990 to 18 in 2006 — an improvement of 1 MPG, or 6% across 17 model years.
Is the Infiniti Q45 efficient for its class?
It ranks 222 of 261 in the Midsize Cars class on current figures, against a class average of 27.3 MPG. That is 9.3 worse than typical for the class.
EPA test figures from fueleconomy.gov. Cost per mile and annual fuel spend are computed at a reference price of $3.20 per gallon — use your own price. Estimates based on official test figures and average fuel prices. Real-world consumption varies with driving style, load, terrain and maintenance.