32 MPG combined from the 2018 GMC Terrain AWD 1.6L diesel might not scream “fuel efficiency champion,” but keep in mind what this vehicle is: a small, but still reasonably substantial and capable, all-wheel-drive SUV. This is a vehicle for those who need a touch of extra traction for winter weather or light off-pavement excursions, and don’t want to sacrifice a comfortable ride or a well-appointed interior to get it. It’s a sensible choice where practicality outweighs outright sportiness, and the diesel engine plays a key role in that balanced equation.

City and highway performance

The EPA estimates for the 2018 GMC Terrain AWD 1.6L diesel show a notable difference between city and highway driving. The city MPG rating comes in at 28, a reasonable figure indicating decent efficiency in stop-and-go traffic. This is largely thanks to the diesel’s inherent low-end torque, meaning less throttle input to get moving. On the open road, the Terrain shines, achieving a respectable 38 MPG on the highway. This suggests that the 6-speed automatic transmission is well-matched to the engine, allowing for relaxed cruising at lower RPMs, maximizing fuel economy during longer journeys. The target customer here doesn’t focus solely on in-town MPG; they’re equally concerned with road trip costs and overall range.

Annual fuel cost

The EPA estimates that the annual fuel cost for the 2018 GMC Terrain AWD 1.6L diesel will be approximately $1,750. This figure is based on driving 15,000 miles per year, with a certain percentage of those miles split between city and highway driving scenarios. The calculation also uses the national average fuel prices at the time of testing. Individual results will vary depending on driving habits and local fuel costs, but the $1,750 projection provides a solid baseline for budgeting purposes. For comparison, owners should explore all Gmc fuel economy data to see how this model compares to its stablemates.

Real-world expectations

While the EPA provides a standardized measure of fuel economy, real-world MPG can vary. Factors such as driving style, terrain, weather conditions, and vehicle load all play a role. Aggressive acceleration, hilly routes, strong headwinds, and carrying heavy cargo will all negatively impact fuel efficiency. Regular maintenance, including proper tire inflation and timely oil changes, is essential to maintaining optimal fuel economy.

Owners report that achieving the EPA’s 38 MPG highway figure is certainly attainable with conscious driving habits, but the city figure may be more challenging to consistently replicate, especially in dense urban environments.

How it compares

In the context of the compact SUV market, the 2018 Terrain diesel’s fuel economy holds up relatively well, but the exact comparison depends on what the buyer prioritizes. A similarly equipped gasoline-powered all-wheel drive Honda CR-V, for example, achieves around 29 MPG combined. The diesel Terrain offers 3 MPG better than that while sacrificing that classic Honda refinement many owners prefer. A Toyota RAV4 Hybrid, with its all-wheel drive and hybrid powertrain, betters the Terrain handily at around 40 MPG combined, but at a higher upfront cost and potentially less comfortable highway cruising due to the CVT. The Terrain offers a unique blend of efficiency and capability that sits between pure economy models and more spacious, thirsty SUVs. Reviewing TERRAIN MPG across all years can further illuminate this balance relative to other model years. The Chevrolet Equinox shares a platform with the GMC Terrain, making some trim levels of that another viable option, but even it’s diesel option is not always chosen over the more powerful gasoline engine.

Tips to maximize efficiency

The diesel engine in the 2018 Terrain rewards a smooth and steady driving style. Avoid aggressive acceleration and hard braking, opting instead for gentle inputs that allow the engine to operate within its most efficient range. Pay attention to the road ahead and anticipate traffic flow to minimize unnecessary speed changes.

Proper tire inflation is critical for fuel economy. Check your tire pressure regularly and ensure that it matches the recommended level specified on the driver’s side doorjamb. Underinflated tires create more rolling resistance, which reduces fuel efficiency. Even a few PSI can make a difference, especially on long drives.

Reduce unnecessary weight. Carrying extra cargo adds strain to the engine, leading to increased fuel consumption. Remove any items from the vehicle that aren’t essential, particularly heavy objects. The Terrain is capable, but it’s still tuned for fuel economy, so lightening the load helps.

Minimize idling. Diesel engines, while fuel-efficient overall, still consume fuel when idling. If you anticipate being stationary for more than a minute or two, turn off the engine. Modern diesel engines are designed to restart easily, and this small step can save a noticeable amount of fuel over time, especially in city driving.