2018 Chevrolet Corvette

This Preliminary Information communication provides information to the technician on the steps need to diagnose and repair vehicles that may have stalling shudder and/or hard shifting into 1st gear or reverse vibration on launch (with excessive crankshaft end play). Technician will test to determine if the crank shaft end play is within specification 0.0015–0.0086 inch. If end play is found to be out of specification, remove engine and inspect for possible crankshaft thrust bearing and/or crankshaft for wear. Inspect thrust bearing for wear on one side and crankshaft on that “mating” surface. If the thrust bearing has three vertical channels worn off replace connecting rod bearings, main bearings, thrust bearing and crankshaft. If working on a Corvette the oil tank with lines and oil cooler are both required to be replaced if equipped

This Preliminary Information communication provides information to the technician about vehicle's odometer appears to be inaccurate relative to a known distance traveled. Technician should obtain a hand-held GPS unit to test the odometer. If a hand held GPS unit is not available, the only other option is to verify the miles traveled using a surveyor's wheel or a dynamometer.

This Preliminary Information communication provides information to the technician about vehicles that in the radio settings some of the vehicle personalization selections within the Comfort and Convenience menu are missing at times. Technician will need to perform a scan for Diagnostic Trouble Codes. Technician will need to follow published Service Information diagnostics if there are Diagnostic Trouble Codes present. If the concern is and intermittent this Preliminary Information communication will be updated with a repair. When the personalization selections are not missing from the Comfort and Convenience menu but they are missing from other menus such as the Climate and Air Quality, Collision/Detection Systems, and Lighting menus, refer to bulletin 17-NA-086. Memory seat adjustments may not be available tech will need to perform a Memory Seat Module replacement/programming.