MyLink user interface is intuitive and easy to use
Optional engines offer efficiency and power
Comfortable and upscale interior
Less cargo space behind the back seat than most competitors
Base 1.5-liter is disappointing all around
Price with options runs higher than average for the class
Midrange trims offer fewer standard safety features than competitors
Even the base SL trim of the 2018 Terrain comes with some desirable features, but it has a very limited options menu. Moving up to the SLE gets you access to more options. The SLT adds more luxury features and access to a few higher-end options. Finally, the top-trim Denali has features and options that put it in the near-luxury class, but it comes with a near-luxury price.
The base SL trim can only be had with the turbocharged 1.5-liter four-cylinder engine (170 hp, 203 lb-ft of torque) and a nine-speed automatic transmission, driving the front wheels. Trailering equipment is the only major optional upgrade available for the SL; beyond that it can't be upgraded. In fact, only three paint colors are available, and only white doesn't come with an added cost.
That said, the SL comes with a decent set of standard features, including keyless ignition and entry, cruise control, 17-inch alloy wheels, a leather-wrapped steering wheel, a rearview camera, two USB ports for the front seats, two charging-only USB ports for the rear, front and rear 110-volt power outlets, a 7-inch touchscreen infotainment system, Bluetooth, Apple CarPlay and Android Auto compatibility, and a six-speaker sound system with satellite radio. GM's Teen Driver system and OnStar are also standard.
The SLE trim comes with largely the same standard equipment as the SL, adding an auto-dimming rearview mirror, a compact spare tire and a handful of interior trim-piece upgrades. However, the SLE also gets access to a host of options and packages.
Packages include the Driver Convenience package, which adds a power-adjustable driver seat, heated front seats, dual-zone automatic climate control, roof rails and remote engine start. The Infotainment I package adds an 8-inch touchscreen, a navigation system, a color information display in the gauge cluster, an SD card reader, two extra USB ports in the center console box, and a 110-volt outlet for the rear seat. The Driver Alert I package adds heated mirrors, blind-spot monitoring, rear cross-traffic alert and rear parking sensors. Some of these add-ons can be had individually, along with a panoramic sunroof and trailering equipment.
Stepping up to the SLT trim gets you leather upholstery and the Driver Convenience and Infotainment I package (except for navigation). Upgrades for the SLT include the Driver Alert I package and the Driver Alert II package, which adds low-speed forward collision warning and mitigation with automatic braking, lane departure warning with lane keeping assist, and automatic high beams. The Infotainment II package adds navigation and a seven-speaker Bose stereo system. Also available is the Preferred package, which includes a power liftgate, driver-seat memory settings, a power passenger seat and a heated steering wheel.
Two gas engines are available for the Terrain. The 1.5-liter engine with front-wheel drive comes standard on both the SLE and SLT trims, but both can be optioned with either a more powerful gasoline engine or a more efficient diesel. The more powerful gas engine, a turbocharged 2.0-liter four-cylinder (252 hp, 260 lb-ft of torque), is available and comes with dual exhaust tips and larger wheels. Also available is a turbocharged 1.6-liter diesel-powered four-cylinder engine (137 hp, 240 lb-ft of torque), paired with a six-speed automatic transmission. GMC estimates the diesel will return 40 mpg highway. Equipping the diesel engine also adds the Driver Convenience package for the SLE and the Preferred package for the SLT.
All three engines come standard with front-wheel drive, but they can be optioned with all-wheel drive. A knob in AWD-equipped Terrains allows drivers to switch between all-wheel drive and front-wheel drive on the fly.
At the top of the Terrain range is the Denali, which can only be had with the 2.0-liter engine. The Denali receives unique styling cues and interior trim, as well as Denali-specific 19-inch wheels and LED headlights. It bundles in the Preferred package and Driver Alert I package, along with several other options such as the panoramic sunroof.
Optional extras for the Terrain Denali include the Driver Alert II package, along with the Advanced Safety package, which adds a surround-view parking camera system and an automated parking system. The Denali's Comfort package adds ventilated front seats and heated rear seats, as well as a wireless phone charging pad.