2023 GMC Sierra 1500: What to check before buying

The 6.2L V8 seizes without warning, often at highway speed. The truck loses propulsion, drops into neutral, and will not restart, and steering can turn heavy. Dealers report metal shavings in the oil, damaged bearings and crankshafts, and lifter failures. Most failures cluster between about 15,000 and 36,199 miles, and one happened at 2,872. Several engines failed after the recall remedy of an inspection and heavier oil, and some replacement engines also failed. Replacement engines are often back-ordered. Heavy oil consumption is also reported. One report is crash-related.

Most filings concern recall 25V274000 rather than an actual breakdown. Owners receive the notice and then wait, because the recall parts are not yet available. Many say the remedy, an inspection and a switch to thicker oil, is only a temporary fix. Some reports do describe real failures: sudden power loss going uphill, a failed engine block, and metal found in the oil. One fuel module failure at 9,000 miles stalled the truck twice, and the part was back-ordered.

The 10-speed transmission locks the rear wheels at speed. In the one crash-related report, the truck veered across lanes. Other reports describe hard, clunking downshifts from 2nd to 1st, slamming into gear, slow response, and limp mode with code P0747. Dealers often replace the valve body, at mileages such as 22,000 and 28,000, and the part is sometimes on national back order. Other filings here repeat the 6.2L engine seizures, including after the recall oil change. Coolant control valve faults also cause overheating and crawling speeds.

The power tailgate opens on its own, sometimes while driving. Infotainment faults are common: audio cuts out along with the safety chimes, screens freeze or reboot, and camera views stall. Some owners tie these problems to an over-the-air update. OnStar units die, and one instrument cluster went fully dark. A failed fuel pump control module shuts the engine off on the interstate. Other reports include a fully drained battery, a chafed main wiring harness, and one fire that started in the cabin while the truck was parked.

The upper grille trim between the hood and grille breaks loose at highway speed. It strikes and cracks windshields, scratches paint, and flies into traffic behind the truck. Owners find broken plastic clips. Many say a recall covers the same part on 2022 trucks, but dealers tell them 2023 trucks are excluded. Some notice the panel getting loose before it falls off. A smaller group reports the tailgate dropping while driving and damaging itself. The tailgate recall covers only trucks from one plant.

Power steering assist cuts out while driving, leaving the wheel very hard to turn. A Service Power Steering message usually appears, along with stability control and restraint warnings. Some wheels lock mid-turn, and some will not move after a cold night. Others fail to return to center coming out of curves. Dealers often cannot reproduce the fault, and one truck logged lost communication with the power steering module repeatedly. One crash report says the engine died during Super Cruise and the truck left the interstate. One fire-related report describes smoke and widespread electrical failures.

Power brake assist fails on the highway. A Brake System Failure message appears with a top-speed limit, the pedal sinks, and the truck becomes very hard to stop. ABS, traction control, and check engine lights come on together. Dealers find communication codes across many systems, and software updates do not always fix it. One case was blamed on a faulty battery. Some owners report the rear brakes locking at 65 to 75 mph. The crash-related report involves the electric parking brake engaging while the truck was towed behind an RV.

The reverse lights are too dim to light the backup camera view at night. The sealed LED housings cannot be fitted with brighter bulbs, so the whole fixture would need replacing. One owner nearly backed over a child. Other reports describe headlights and fog lights caking over with snow and a narrow headlight beam that leaves dips in the road dark. High beams and wipers cutting out together for about 30 seconds and flickering daytime running lights also appear.

The engine loses power and stalls without warning, often with no check engine light. It then cranks but will not restart, even with plenty of fuel in the tank. Dealers trace this to the fuel pump control module, and owners describe parts backlogs of about three months. Stalling in traffic leaves trucks stranded partly in the lane. A separate complaint describes fuel sloshing that thumps when the truck stops. A service bulletin calls the noise normal.