November 7, 2014

A rattle noise at the engine bell housing may be heard on some 2014-2015 Corvettes built with the 6.2L engine (RPO LT1) and an automatic transmission.

Follow the appropriate Service Information diagnostic procedures to determine if the rattle noise is coming from the Driveline Support Assembly (DSA) or the transmission flex plate.
If the rattle is coming from the flex plate, it will only be heard at idle from the front of the vehicle while in Park.

If it’s determined that the rattle noise is coming from the flex plate (Fig. 7), raise the vehicle on a hoist and pull the front bell access cover. The noise will be coming from the hole.

TIP:
Check that the pinch clamp bolt is tight before replacing the front flex plate. The loose bolt condition results in the same noise.
This is an easy check before starting a major service procedure.

Do not reinstall the old flex plate even if it looks OK as the cause of the rattle may not be visible.

Unlike the flex plate rattle, a DSA rattle noise typically occurs at or just off idle and will be louder when observed via the rear bell housing access plug.

When performing repairs for a flex plate rattle or DSA rattle, refer to the latest information in the Service Information:

• #13-04-17-001 – Driveline Support (Torque Tube) / Propeller Shaft Input to Front Hub Bearing Alignment

• Document ID 3973764 – Driveline Support Assembly Replacement (with Automatic Transmission)