INEOS Automotive Grenadier Fuel Economy (MPG)

Name: INEOS Automotive Grenadier MPG & Fuel Economy
Creator: AutoSpecData
License: https://creativecommons.org/licenses/by/4.0/

What is the real-world gas mileage of a 2025 INEOS Automotive Grenadier?

The 2025 INEOS Automotive Grenadier gets up to 15 MPG combined (15 city / 15 highway) in EPA testing.

Latest model year (2025):

The INEOS Automotive Grenadier gets up to 15 MPG combined (15 city / 15 highway) in the Auto (S8), 6 cyl, 3.0 L trim.

Verifiedfueleconomy.gov · Verified August 11, 2026

Overview MPG Engine Specs Fuel Cost Transmission Drivetrain Vehicle Class Maintenance

INEOS Automotive Grenadier MPG — All Years

Year	Trim	Engine	Fuel	City (MPG)	Hwy (MPG)	Combined (MPG)
2025Config 1 of 2	Auto (S8), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	15	15	15
2025Config 2 of 2	Auto (S8), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	14	14	14
2024Config 1 of 2	Auto (S8), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	15	15	15
2024Config 2 of 2	Auto (S8), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	14	14	14
2023Config 1 of 2	Auto (S8), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	15	15	15
2023Config 2 of 2	Auto (S8), 6 cyl, 3.0 L	6 3.0L	Premium Gasoline	14	14	14

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.

INEOS Automotive Grenadier data analysis

How INEOS Automotive Grenadier combined fuel economy varies

Across 6 configurations recorded for the 2023 through 2025 INEOS Automotive Grenadier, combined fuel economy runs from 14 MPG to 15 MPG. The strongest figure belongs to the 2023 INEOS Automotive Grenadier (Auto (S8), 6 cyl, 3.0 L) at 15 MPG, and the weakest to the 2025 car (Auto (S8), 6 cyl, 3.0 L) at 14 MPG — a spread of 7%. The narrow spread means any year of the INEOS Automotive Grenadier in this table behaves much like the others, so you can shop on price, condition and mileage rather than chasing a particular model year.

What changed for 2025

Average combined fuel economy for the 2025 INEOS Automotive Grenadier is 14.5 MPG, against 14.5 MPG for the 2024 car — it held flat. A carry-over year like this usually means no powertrain or structural change, so an older example is the cheaper way into the same specification.

How to read this INEOS Automotive Grenadier data

This page lists every 2023 through 2025 INEOS Automotive Grenadier record we hold for this measurement — 6 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.

Where these INEOS Automotive Grenadier 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 INEOS Automotive Grenadier 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	15 MPG	15 MPG	0%
65 mph	15 MPG	13.7 MPG	9%
70 mph	15 MPG	12.5 MPG	17%
75 mph	15 MPG	11.5 MPG	24%
80 mph	15 MPG	10.5 MPG	30%

Our Real-World Speed MPG Adjuster re-scales the INEOS Automotive Grenadier 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 Grenadier MPG

What is the MPG of the INEOS Automotive Grenadier?

The INEOS Automotive Grenadier gets up to 15 MPG combined (15 city / 15 highway) in the 2025 model year. Fuel economy varies by engine and trim — see the full table above for details.

Which INEOS Automotive Grenadier trim has the best fuel economy?

The Auto (S8), 6 cyl, 3.0 L trim offers the best combined fuel economy at 15 MPG. Smaller engines and front-wheel-drive configurations typically achieve the highest MPG.