2018 head-to-head · Midsize Car
2018 Audi S8 vs Cadillac CTS-V
MPG, range and what each one really costs you to fuel, from official EPA ratings and recalculated with your own gas and electricity prices.
AWD · 4.0L 8-cyl turbo · 8-speed automatic · 18 MPG
RWD · 6.2L 8-cyl supercharged · 8-speed automatic · 17 MPG
The 2018 Audi S8 is the cheaper one to run. Driving 15,000 miles a year with $3.95/gal premium gas, it costs about $3,292 a year to fuel (18 MPG), versus $3,485 for the 2018 Cadillac CTS-V (17 MPG). That's roughly $194 a year, or about $968 over five years.
Your numbers
Change these to match your driving and local prices. Every figure and chart on this page updates.
Fuel cost over 10 years
- Audi S8
- Cadillac CTS-V
Side by side
| Audi S8 | Cadillac CTS-V | |
|---|---|---|
| $3,292 | Your annual fuel cost | $3,485 |
| 18 MPG | Combined efficiency | 17 MPG |
| 14 MPG | City | 14 MPG |
| 24 MPG | Highway | 21 MPG |
| 100 cu ft | Passenger volume | 97 cu ft |
| 15 cu ft | Cargo volume | 13 cu ft |
| 503 g/mi | Tailpipe CO₂ (g/mi) | 530 g/mi |
| 3/10 | EPA fuel economy score | 3/10 |
| 3/10 | EPA greenhouse gas score | 3/10 |
| Gas | Powertrain | Gas |
| Premium gasoline | Fuel | Premium gasoline |
| 4.0L 8-cyl turbo | Engine / motor | 6.2L 8-cyl supercharged |
| 8-speed automatic | Transmission | 8-speed automatic |
| AWD | Drivetrain | RWD |
✓ marks the better value. EPA scores run 1–10 (10 is best). Volumes come from the EPA interior volume index and aren't published for every body style.
Audi S8 vs Cadillac CTS-V across model years
- Audi S8
- Cadillac CTS-V
Annual fuel cost of the most efficient configuration of each model year, at your prices. Click a point to open that year.
How they differ
Per EPA interior volume figures, the Audi S8 has more passenger space (100 vs. 97 cu ft); the Audi S8 has more cargo space (15 vs. 13 cu ft).
Among 74 2018 midsize cars, the Audi S8 ranks 67th and the Cadillac CTS-V 70th for lowest fuel cost.
Frequently asked questions
Which is more fuel-efficient, the 2018 Audi S8 or the 2018 Cadillac CTS-V?
Measured by cost to drive, the Audi S8. The Audi S8 is rated 18 MPG combined and the Cadillac CTS-V 17 MPG (EPA, most efficient configuration of each).
How much does it cost to fuel the 2018 Audi S8 vs. the Cadillac CTS-V per year?
At 15,000 miles a year with $3.95/gal premium gas, about $3,292 for the Audi S8 and $3,485 for the Cadillac CTS-V.
Which has more cargo space?
The Audi S8, with 15 cu ft of luggage volume versus 13 cu ft (EPA interior volume index).
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