GMC Terrain vs Mercedes-Benz GLC-Class: Specs Compared

Also searched as Mercedes-Benz GLC-Class vs GMC Terrain specs — both orientations show this same side-by-side comparison.

The GMC Terrain is the more efficient of the two: it reaches 32 mpg combined versus 29 mpg for the Mercedes-Benz GLC-Class, a 3 mpg advantage and costs about $400 less per year to fuel.

Across 5 measured categories, the GMC Terrain leads in 4. Figures are EPA test data, not manufacturer claims.

2015–2027

GMC Terrain

Small Sport Utility Vehicle 2WD · 47 configurations

32mpg combined (best)
All GMC Terrain specs

2016–2027

Mercedes-Benz GLC-Class

Small Sport Utility Vehicle 4WD · 72 configurations

29mpg combined (best)
All Mercedes-Benz GLC-Class specs

Head-to-head specifications

MetricGMC TerrainMercedes-Benz GLC-Class
Best combined MPG32 mpg ✓29 mpg
Best city MPG28 mpg ✓26 mpg
Best highway MPG39 mpg ✓33 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$2,200 ✓$2,600
Lowest CO2 output316 g/mi84 g/mi ✓
Engines offeredSIDI, 1.6, SIDI; FFVSIDI; Mild Hybrid, SIDI; PHEV, SIDI
TransmissionsAutomatic 8-spd, Automatic (variable gear ratios), Automatic 9-spdAutomatic 9-spd, Automatic 7-spd, Automatic (S9)
DrivetrainsAll-Wheel Drive, Front-Wheel DriveRear-Wheel Drive, All-Wheel Drive, 4-Wheel Drive
Fuel typesRegular, Premium, DieselPremium, Premium and Electricity
EPA classSmall Sport Utility Vehicle 2WDSmall Sport Utility Vehicle 4WD
Years covered2015–20272016–2027
Configurations on record4772

Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.

GMC Terrain vs Mercedes-Benz GLC-Class dimensions and size

The Mercedes-Benz GLC-Class is 4.7 inches longer than the GMC Terrain on a wheelbase 6.7 inches longer, and 646 lbs heavier. Both clear the roughly 200 inches of usable length in a standard single garage bay.

GMC Terrain versus Mercedes-Benz GLC-Class exterior dimensions
DimensionGMC Terrain (2026)Mercedes-Benz GLC-Class (2026)Difference
Length181.1 in185.8 in4.7 in
Width (excl. mirrors)74.4 in74.4 inidentical
Height65.7 in64.6 in1.2 in
Wheelbase107.1 in113.8 in6.7 in
Curb weight3,598 lbs4,244 lbs646 lbs

Width excludes mirrors; add 8–12 inches for mirrors out. Figures are for the newest model year on record for each vehicle. See both drawn to scale.

GMC Terrain vs Mercedes-Benz GLC-Class: what the numbers mean

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the GMC Terrain burns about $2,200 of fuel annually against $2,600 for the Mercedes-Benz GLC-Class. That $400 yearly gap compounds to roughly $2,000 over five years and $3,200 over eight — often more than the price difference between two trims of the same vehicle, and the single largest running-cost line item separating these two.

City and highway economy: the GMC Terrain leads in both cycles — 28 mpg city and 39 mpg highway against 26 and 33 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.

Powertrain choice: the GMC Terrain is recorded with 3 distinct engine configurations (SIDI, 1.6, SIDI; FFV), the Mercedes-Benz GLC-Class with 3 (SIDI; Mild Hybrid, SIDI; PHEV, SIDI). Across 47 recorded GMC Terrain configurations and 72 for the Mercedes-Benz GLC-Class, the wider the engine spread the more the real-world fuel efficiency depends on which version you actually buy, so check the specific model year and drivetrain rather than the headline number.

Drivetrain and class: the GMC Terrain is offered with All-Wheel Drive, Front-Wheel Drive, the Mercedes-Benz GLC-Class with Rear-Wheel Drive, All-Wheel Drive, 4-Wheel Drive. All-wheel drive typically costs one to two mpg combined against the same vehicle in front- or rear-wheel drive, which is worth remembering when the gap between these two is small. The EPA classes them as Small Sport Utility Vehicle 2WD and Small Sport Utility Vehicle 4WD respectively — the class drives the interior volume, cargo space and passenger space each one is measured against.

Tailpipe emissions: at their cleanest configurations the Mercedes-Benz GLC-Class emits 84 g/mile of CO2 versus 316 g/mile for the GMC Terrain. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.

Terrain vs GLC-Class: common questions

Which is better on gas, the GMC Terrain or the Mercedes-Benz GLC-Class?

The GMC Terrain is the more efficient of the two: it reaches 32 mpg combined versus 29 mpg for the Mercedes-Benz GLC-Class, a 3 mpg advantage and costs about $400 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the GMC Terrain runs about $2,200 a year in fuel at its most efficient configuration, versus about $2,600 for the Mercedes-Benz GLC-Class — a difference of roughly $400 per year.

What engines do the Terrain and GLC-Class offer?

GMC Terrain: SIDI, 1.6, SIDI; FFV. Mercedes-Benz GLC-Class: SIDI; Mild Hybrid, SIDI; PHEV, SIDI.

Are they in the same vehicle class?

The EPA classifies the GMC Terrain as Small Sport Utility Vehicle 2WD and the Mercedes-Benz GLC-Class as Small Sport Utility Vehicle 4WD, so they aren't a like-for-like match on size.

More Terrain comparisons

More GLC-Class comparisons

Comparison id: gmc-terrain-vs-mercedes-benz-glc-class