— A GM Vortec engine lawsuit alleges there are problems with the piston rings, PCV systems, active fuel management and oil life monitoring systems.
Those allegedly defective systems are included in these vehicles named in the GM Vortec engine lawsuit.
2010—2014 Chevrolet Avalanche
2010—2014 Chevrolet Silverado
2010—2014 Chevrolet Suburban
2010—2014 Chevrolet Tahoe
2010—2014 GMC Sierra
2010—2014 GMC Yukon
2010—2014 GMC Yukon XL
The Vortec engine lawsuit alleges oil is allowed to travel past the defective piston rings from the crankcase and burns in the combustion chamber during the combustion stroke. A mist of oil and exhaust gas is created by blowby that reaches the crankcase and blends with oil in the crankcase.
The class action lawsuit says the oil mist is then "vacuumed through the engine’s PCV system into the intake manifold where it is recirculated into the combustion chamber and burned, causing additional oil consumption."
This allegedly reduces the amount of oil in the vehicle and causes engine damage due to a lack of proper lubrication of the engine components.
The plaintiffs also claim the spark plugs constantly foul from oil due to the defective piston rings. Oil allegedly coats the electrodes of the spark plugs, which should remain dry to fire properly.
Carbon buildup is also allegedly an issue as oil hardens when it passes around the piston rings and isn't burned in the combustion chamber. The vehicles suffer spark knock and the pre-ignition detonation interferes with the proper seating of the piston rings in their grooves, which causes them to wear out as they grind against the cylinder walls improperly.
Alleged Defects Named in the GM Vortec Engine Lawsuit
According to the class action lawsuit, multiple other components and systems contributes to oil consumption. The active fuel management system comprises an oil pressure relieve valve that sprays oil directly at the piston skirts. This oil spray allegedly fouls the defective piston rings and causes oil to migrate past the rings.
Another alleged problem is the Vortec 5300 PCV system that vacuums atomized oil from the valvetrain into the intake system, where it is ultimately burned in the combustion chambers. This vacuuming process allegedly contributes to excessive oil consumption because the PCV system is flawed.
Then there is the oil life monitoring systems which allegedly fail to warn drivers of low oil levels that could damage the engines. According to the plaintiffs, the systems monitor engine conditions to "calculate the expected deterioration in oil quality and thus the time for a recommended oil change."
This allegedly allows drivers to keep driving the vehicles even though the Vortec engines are undergoing damage due to low oil levels and a lack of engine lubrication.
An "extraordinary number of complaints" have allegedly been filed about GM oil consumption problems in Vortec 5300 engines dating back to model year 2007 vehicles.
The plaintiffs claim there were so many oil consumption complaints GM engineers started investigating in at least 2008, allegedly concluding the piston rings were suffering premature failures. Those failures caused excessive oil consumption and engine wear.
According to the Vortec engine lawsuit, GM must have known about the alleged oil consumption problems because technical service bulletins were issued to dealers.
Those TSBs were related to excessive oil consumption in Generation IV Vortec 5300 engines, and the lawsuit says the bulletins talked about piston ring flaws and problems with the PCV systems and active fuel management systems.
The GM Vortec engine lawsuit was filed in the U.S. District Court for the Eastern District of Wisconsin: Brame, et al., v. General Motors LLC.
The plaintiffs are represented by DiCello Levitt Gutzler LLC, and Beasley, Allen, Crow, Methvin, Portis & Miles, P.C.