08-06-01-019: Rattle/Tapping Type Noise Heard Under Hood (Diagnose and Replace Engine Oil Tank Transfer Tube Seal (O-Ring)) - (Aug 13, 2008)

Models: 2006-2009 Chevrolet Corvette Z06

2009 Chevrolet Corvette ZR1 with 6.2L or 7.0L Engine (VINs R, E -- RPOs LS9, LS7)

Condition

Some customers may comment on a rattle or tapping type noise that is heard under the hood at just above idle, usually 1200 to 2200 RPM.
In some cases, this noise may also be heard on the inside of the vehicle and be more pronounced on the passenger side.

Cause

This noise may be caused by the internal transfer tube in the engine oil tank hitting the inside of the tank cover.
The seal (o-ring) that secures the tube in place may split and slide down the tube allowing the tube to be loose.

Correction

Diagnose the noise by raising the vehicle on a hoist and holding the throttle at about 1500 RPM to duplicate the condition.
Use a stethoscope or chassis ears and place them on the side of the engine oil tank. If the noise is detected, perform the procedure outlined below. If the noise is not detected, continue following published diagnostics in SI.

Remove the engine oil tank from the vehicle. Refer to the Oil Tank Replacement procedure in SI.
Remove the eight bolts that secure the tank top.

Separate the tank. Check the seal (o-ring) for proper position and damage. Replace the seal (o-ring) if damaged with P/N 24576940.

Reinstall the tank top and secure with the eight bolts.
Install the engine oil tank into the vehicle. Refer to the Oil Tank Replacement procedure in SI.

Parts Information Part Number Description Qty

24576940 Seal (O-Ring), Engine Oil (Tank Transfer Tube)