Some owners of 2006-2012 Chevy Corvette Z06 or 2009-2012 ZR1 models may comment on a rattle or tapping noise from under the hood.
The noise is usually heard just above idle at 1,200 to 2,200 rpm. The noise may be more pronounced on the passenger side.
The noise may be caused by the internal transfer tube in the engine’s dry sump oil tank hitting the inside of the tank cover.
The O-ring seal that secures the tube may split and slide down the tube, allowing the tube to be loose.
Diagnose the noise by raising the vehicle on a hoist and holding the throttle at about 1,500 rpm.
Use a stethoscope or chassis ears at the side of the engine oil tank. If the noise is heard, follow these steps:
1. Remove the engine oil tank.
2. Remove the eight bolts that secure the tank top.
3. Separate the tank and inspect the O-ring for position and damage.
If needed, replace the O-ring with part number 24576940.
4. Reinstall the tank top and secure the eight bolts.
5. Install the tank.