Technical Service Bulletin 18186 — 2018 CHEVROLET IMPALA

18186 - Customer Satisfaction Program. Certain 2018 model year Buick Enclave, Chevrolet Impala and Chevrolet Traverse vehicles, equipped with a 3.6L engine (RPO LFX or LFY), may have a condition where the piston oil control ring may have been damaged during installation. If this happened, it could lead to excess oil consumption in the combustion chamber and result in an engine misfire, a check engine light, and low oil levels. If the vehicle continues to be driven with an insufficient oil level, the engine could be severely damaged and the vehicle could lose propulsion. Dealers are to inspect cylinders 2, 4, and 6. If, during inspection, the technician sees evidence of cylinder wall scoring, (gouges), or a broken oil control ring is found, dealers are to replace the engine.