Stage 8 8966A GM V6 Flexplate Bolt Locking Fastener Kit

The Stage 8 8966A is a GM V6 Flexplate Bolt Kit featuring Stage 8's patented active mechanical locking fastener system. This kit includes four (4) 7/16-20 x 11/16 Grade 8, 6-point hex bolts engineered to secure the flexplate on GM V6 engines — including Chevrolet and Pontiac applications — and prevent loosening caused by vibration, thermal expansion, and contraction.

How It Works:

Each bolt features a unique precision-machined groove on the bolt head. After torquing the bolt to specification, a locking retainer is slipped over the bolt head and a snap-ring E-clip is seated into the groove. The retainer braces against an adjacent fixed component, physically preventing the bolt from rotating loose — no thread-locking compounds or adhesives required.

Kit Includes:

• (4) 7/16-20 x 11/16 in. Grade 8, 6-point hex locking flexplate bolts
• Locking retainers and E-clip snap rings
• All hardware necessary for installation

Key Features:

• Patented active mechanical locking system — fail-safe when installed as directed
• Unaffected by shock, vibration, or thermal cycling — maintains clamping force under extreme conditions
• No adhesives or thread lockers needed — purely mechanical retention
• Fully reusable and removable — can be serviced without replacing hardware
• Visually inspectable — confirm locked status at a glance
• Grade 8 steel construction — natural finish, high-strength hardware
• Made in the USA

Stage 8 locking flexplate fasteners are a critical upgrade for performance builds and high-mileage vehicles where flexplate bolt loosening can lead to drivetrain noise, vibration, or catastrophic transmission damage. Designed as a direct replacement for OEM fasteners, the 8966A installs with standard tools plus snap ring pliers.