NHTSA Complaint #11570670 — 2017 GMC YUKON XL

The 'active fuel management/displacement on demand' lifters failed and caused the engine to run very poorly with a significant lack of power. This occurred while driving and could have caused a crash before I was able to get off the road and out of the way of traffic. The problem was diagnosed and confirmed by an independent repair shop. The vehicle had to have the camshaft and all valve lifters replaced, as well as several valves that were damaged in the failure. The total cost to repair was just over $9000. The failure also caused the catalytic converters to become clogged, resulting in even further loss of power from the engine. There were no warning lamps or symptoms prior to the failure. It occurred suddenly as I was driving down the road. Searching online reveals this seems to be a common problem with GM 5.3 and 6.2l engines from 2010 onward. GM is aware of the issues and refuses to assist in any way. Their only response is that the vehicle is "Out of warranty". The failure is caused by a design defect in the AFM/DOD system that starves the lifters of oil, resulting in lifter failure and damage to the camshaft and valves.