2004 Corvette: GM TechLink: Seatbelt Retractor
From GM TechLink, October 2004:
Owners of some 2004 Chevrolet Corvettes may state that the driver or passenger seatbelt will not extend from the seatbelt retractor.
If a resolution can't be found through normal diagnosis, replace the affected seatbelt and install a new bolt (p/n 15017724) and new washer (p/n10257765) and discard the original bolt and washer. The larger diameter washer distributes the clamping load evenly on the lower seatbelt retractor.
- Thanks to Paul Radzwilowicz