The old 2.4L that quietly drinks oil — worth buying only with a documented timing-chain history.

The oil problem above is what kills the chain. Three independent mechanics working on this exact engine describe the same sequence: the chain stretches, the tensioner runs out of travel to compensate, and the chain slaps around inside the timing case. One notes the noise typically starts around 65,000 miles; another says that if it goes far enough the chain will "jump a tooth and pretty much wipe out" the engine, because this is an interference design where the valves and pistons occupy the same space at different moments. Listen on a genuinely cold start: a rattle lasting five to thirty seconds that fades as oil pressure builds is the classic tell. Mechanics do the timing chain, the balance chain and the water pump together, because the water pump is driven off the same chain and they wear at the same rate.

A cold-weather failure that mechanics see repeatedly and owners confirm. The PCV system — positive crankcase ventilation, the plumbing that lets pressure escape the bottom of the engine — can freeze with water vapour while the engine is warming up. Pressure then builds with nowhere to go and pushes out a main seal. One 2016 owner in this year's file describes exactly that at about 75,000 miles: the crankcase valve froze, pressure built and the rear main seal let go. Another reports a blown rear main seal alongside a locked-up drivetrain. Confirming this is easy and worth doing: look for oil weeping where the engine meets the transmission. GM's own coverage for this mechanism, tied to the same oil consumption, was written for the 2010 to 2013 cars only.

This is the single largest complaint tag on the 2016 Terrain, and it is the one piece of genuine good news here. The ball joints inside the front wiper module corrode and wear until one separates from its socket, at which point one or both wipers simply stop. GM covers it under Special Coverage 10232660 and 10219642 — a Special Coverage is GM's extended-warranty program for a specific known defect, performed free — with dealers inspecting the wiper assembly and replacing the linkage or the whole module. The 2016 and 2017 Terrain are both named. Run the wipers through every speed on the test drive, and ask the dealer whether this work has already been claimed against the car.

A GMC-only campaign that the twin Chevrolet Equinox does not share. The headlight housings throw a reflection above the beam pattern and outside the driver's own view, bright enough that NHTSA judged the car non-compliant with the federal lighting standard. The risk is to oncoming drivers rather than to you. Dealers fit headlamp appliques free of charge, and letters went out in September 2022 — which means plenty of cars changed hands before the owner ever saw one. It costs nothing to check and nothing to fix.