Against 399 other V6 cars rated 2018–2020, the CT6 trails their 21.7 mpg average by 2.7 mpg, about $251 a year. Averaged over the years each was sold, the most economical engine since 2016, the 2L 4-cyl (2016–2019), does 25.8 mpg and the thirstiest, the 4.2L 8-cyl (2019–2020), 17: $771 a year apart.
Every Cadillac CT6 engine, compared
Yearly cost assumes 12,000 miles at $3.20 a gallon.
| Engine | Combined | City / Highway | Years | Fuel per year |
|---|---|---|---|---|
| 2L 4-cyl | 22.5 / 31 | 2016–2019 | $1,488 | |
| 2L 4-cyl Hybrid | 23 / 29 | 2017–2018 | $1,506 | |
| 3L 6-cyl | 18 / 26 | 2016–2018 | $1,829 | |
| 3.6L 6-cyl | 18 / 27 | 2017–2020 | $1,829 | |
| 4.2L 8-cyl | 14 / 25 | 2019–2020 | $2,259 |
What that actually costs
Against its rivals in the same model years, the Dodge Charger gets 21 mpg, the Kia K5 32 mpg and the Porsche Panamera 21.2 mpg, next to 19 mpg for the 2020 CT6. The CT6 costs the most of them to run: $821 a year more than the Kia K5.
| Measure | Value |
|---|---|
| Cost per mile (2020) | $0.168 |
| Fuel per year | $2,021 |
| Fuel over five years | $10,105 |
| Against other V6 cars, 2018–2020 | +$251 a year |
| EPA's own estimate | $3,288 a year |
City or highway — who is this car for
The 2020 Cadillac CT6 gives up 10 mpg in town: 26 on the highway against 16 in the city, $923 a year if every mile were city driving.
| Measure | Value | Reading |
|---|---|---|
| City (2020) | 16 mpg | $2,400 a year if you only drive in town |
| Highway | 26 mpg | $1,477 a year if you mostly commute |
| Gap | +10 mpg (63%) | Wide — this car dislikes traffic |
How the CT6 changed over the years
The CT6 peaked in 2017 at 24 mpg (21 city, 28.7 highway) and was at its thirstiest in 2020 at 19 — 5 mpg apart, or $421 a year in fuel between buying one year and the other. The 2020 car does 19. The 2020 model loses 3 mpg against 22 for the 2019, with 2 versions instead of 3.
| Model year | Combined | City / Highway | Engines offered | Fuel per year |
|---|---|---|---|---|
| 2020 | 16 / 26 | 2 | $2,021 | |
| 2019 | 18.7 / 28.7 | 3 | $1,745 | |
| 2018 | 21 / 28.3 | 3 | $1,620 | |
| 2017 | 21 / 28.7 | 3 | $1,600 | |
| 2016 | 20 / 28 | 2 | $1,670 |
MPG is a number. Dollars per year is the answer.
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How we count
This page rests on 13 EPA ratings of the Cadillac CT6 — 5 engines across 2016–2020. 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 $3,288. Full method.
Frequently asked questions
What mpg does the 2020 Cadillac CT6 get?
19 mpg combined, 16 city and 26 highway, per EPA; its 2 versions that year range from 17 to 21. Across every year since 2016 the CT6 has averaged 22.5 mpg.
Is the 2020 CT6 more efficient than the 2019?
No: 19 against 22 mpg combined, about $276 a year more to run.
Which CT6 year has the best gas mileage?
The 2017, at 24 mpg combined (21 city, 28.7 highway).
Does the CT6 get better gas mileage than the Dodge Charger?
No: 19 mpg for the 2020 CT6 against 21 for the 2021 Dodge Charger, about $192 a year more to run.
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