Cadillac CT6 Fuel Economy (MPG)

Name: Cadillac CT6 MPG & Fuel Economy
Creator: AutoSpecData
License: https://creativecommons.org/licenses/by/4.0/

What is the real-world gas mileage of a 2020 Cadillac CT6?

The 2020 Cadillac CT6 gets up to 28 MPG combined (24 city / 34 highway) in EPA testing.

Latest model year (2020):

The Cadillac CT6 gets up to 21 MPG combined (18 city / 27 highway) in the Auto (S10), 6 cyl, 3.6 L trim.

Verifiedfueleconomy.gov · Verified August 9, 2026

Overview MPG Engine Specs Fuel Cost Transmission Drivetrain Vehicle Class Maintenance Dimensions Curb Weight EV Range

Cadillac CT6 MPG — All Years

Year	Trim	Engine	Fuel	City (MPG)	Hwy (MPG)	Combined (MPG)
2020Config 1 of 2	Auto (S10), 6 cyl, 3.6 L	6 3.6L	Regular Gasoline	18	27	21
2020Config 2 of 2	Auto (S10), 8 cyl, 4.2 L	8 4.2L	Premium Gasoline	14	25	17
2019Config 1 of 4	Auto (S10), 4 cyl, 2.0 L	4 2.0L	Premium Gasoline	24	34	28
2019Config 2 of 4	Auto (S10), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	18	26	21
2019Config 3 of 4	Auto (S10), 6 cyl, 3.6 L	6 3.6L	Regular Gasoline	18	27	21
2019Config 4 of 4	Auto (S10), 8 cyl, 4.2 L	8 4.2L	Premium Gasoline	14	25	17
2018Config 1 of 4	Auto (S8), 4 cyl, 2.0 L	4 2.0L	Premium Gasoline	22	30	25
2018Config 2 of 4	Auto (S8), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	18	26	21
2018Config 3 of 4	Auto (S8), 6 cyl, 3.6 L	6 3.6L	Regular Gasoline	18	27	21
2018Config 4 of 4	Auto (variable gear ratios), 4 cyl, 2.0 L	4 2.0L	Premium Gasoline	23	29	25
2017Config 1 of 4	Auto (S8), 4 cyl, 2.0 L	4 2.0L	Premium Gasoline	22	30	25
2017Config 2 of 4	Auto (S8), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	18	26	21
2017Config 3 of 4	Auto (S8), 6 cyl, 3.6 L	6 3.6L	Regular Gasoline	18	27	21
2017Config 4 of 4	Auto (variable gear ratios), 4 cyl, 2.0 L	4 2.0L	Premium Gasoline	23	29	26
2016Config 1 of 3	Auto (S8), 4 cyl, 2.0 L	4 2.0L	Regular Gasoline	22	30	25
2016Config 2 of 3	Auto (S8), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	18	26	21
2016Config 3 of 3	Auto (S8), 6 cyl, 3.6 L	6 3.6L	Regular Gasoline	18	27	21

Data sourced from fueleconomy.gov (U.S. Department of Energy). MPG figures are EPA-tested. Fuel costs are estimates based on average fuel prices and 15,000 miles/year.

Cadillac CT6 data analysis

How Cadillac CT6 combined fuel economy varies

Across 17 configurations recorded for the 2016 through 2020 Cadillac CT6, combined fuel economy runs from 17 MPG to 28 MPG. The strongest figure belongs to the 2019 Cadillac CT6 (Auto (S10), 4 cyl, 2.0 L) at 28 MPG, and the weakest to the 2020 car (Auto (S10), 8 cyl, 4.2 L) at 17 MPG — a spread of 65%. A gap that wide means the model year and configuration you buy matter more than the nameplate does: quoting a single number for the Cadillac CT6 would be misleading.

What changed for 2020

Average combined fuel economy for the 2020 Cadillac CT6 is 19 MPG, against 21.8 MPG for the 2019 car — it fell by 2.8 MPG. Buyers who care most about this figure should look at the earlier model years in the table above before assuming newest is best.

How to read this Cadillac CT6 data

This page lists every 2016 through 2020 Cadillac CT6 record we hold for this measurement — 17 rows in total, one per configuration and model year rather than a single headline figure. Figures are published as the source agency records them: we do not round, average or interpolate missing years, and a year that is absent from the table is a year with no published measurement rather than a zero. Where a manufacturer offered several drivetrains or body styles in the same year, each appears on its own row, because those variants rarely share the same numbers.

Configurations behind these Cadillac CT6 numbers

The 2016 through 2020 Cadillac CT6 entries here cover variants including Auto (S10), 6 cyl, 3.6 L, Auto (S10), 8 cyl, 4.2 L, Auto (S10), 4 cyl, 2.0 L, Auto (S10), 6 cyl, 3.0 L, Auto (S8), 4 cyl, 2.0 L, Auto (S8), 6 cyl, 3.0 L, Auto (S8), 6 cyl, 3.6 L and Auto (variable gear ratios), 4 cyl, 2.0 L. 2019 is the busiest model year in the record with 4 separate measured configurations, which is why a single quoted combined fuel economy figure for that year is rarely the one that matches the car in front of you. Match the row to the exact drivetrain, body style and engine on the window sticker or VIN before relying on the number, and use the comparison links below to see how those same configurations line up against rival models.

Where these Cadillac CT6 figures come from

Every value on this page is loaded from federal open data — EPA fuel economy submissions, NHTSA vehicle and crash-test records, and manufacturer specification filings — rather than dealer listings or copied editorial content. The Cadillac CT6 record refreshes as the agencies publish, which typically means new model-year rows appear in the autumn and crash-test results follow through the model year as vehicles are tested. Because certification data is filed per configuration, treat any single headline number for this vehicle with caution: the figure that applies to a specific car depends on its engine, drivetrain, body style and model year, all of which are listed separately above. If a number here disagrees with a brochure, the brochure is usually quoting the best available configuration rather than the one being sold.

Official Factory Specs vs. AutoSpecData Expert Benchmarks

The EPA highway loop never holds interstate speed. Here is what the same engine does when you sit on the cruise control.

Cruise speed	EPA highway spec	AutoSpecData adjusted MPG	Fuel you lose
60 mph	34 MPG	34 MPG	0%
65 mph	34 MPG	31.7 MPG	7%
70 mph	34 MPG	29.5 MPG	13%
75 mph	34 MPG	27.5 MPG	19%
80 mph	34 MPG	25.6 MPG	25%

Our Real-World Speed MPG Adjuster re-scales the Cadillac CT6 EPA highway result with a quadratic drag term (mpg = hwy ÷ (1 + k·(v² − 60²)/60²), k = 0.55 for trucks, SUVs and vans, 0.42 for cars). Wind, roof racks, and a heavy right foot make it worse, never better.

Frequently Asked Questions About CT6 MPG

What is the MPG of the Cadillac CT6?

The Cadillac CT6 gets up to 28 MPG combined (24 city / 34 highway) in the 2020 model year. Fuel economy varies by engine and trim — see the full table above for details.

Which Cadillac CT6 trim has the best fuel economy?

The Auto (S10), 4 cyl, 2.0 L trim offers the best combined fuel economy at 28 MPG. Smaller engines and front-wheel-drive configurations typically achieve the highest MPG.