1985-1996 C4 Header and Pillar Weatherstrip Retainer Pin Kit 12503854 - OEM Number(s) (12503854,25016383)
Ensure correct weatherstrip mounting with this OE-style C4 weatherstrip pin kit. Designed specifically for 1985–1996 C4 Coupes and Convertibles, this 6-piece pin set restores factory-correct attachment for your windshield header and pillar post weatherstrip. GM originally used two different pin types—four in the lower pillar post and two across the upper windshield header. This reproduction kit matches that configuration precisely, securing the seal without damaging your Corvette’s original mounting surfaces.
Fits Corvette Models as Follows
• 1985–1996 C4 – Coupe and Convertible
Features
• Replaces GM part numbers 12503854 and 25016383
• Kit includes 6 weatherstrip pins—4 lower pillar, 2 upper header
• OE-style plastic head pins prevent weatherstrip distortion
• Exact-fit reproduction for C4 pillar and header locations
• Compatible with original and reproduction weatherstrip seals
Kit Contents
• (4) Lower Pillar Post Weatherstrip Pins – GM 12503854
• (2) Upper Windshield Header Weatherstrip Pins – GM 25016383
Dimensions and Weights
• Lower Pin Length: 0.625 in
• Upper Pin Length: 0.750 in
• Total Kit Weight: <1 oz
Tech Notes
• Pin head diameter and shaft length match factory originals for secure hold without compression distortion
• Designed to work with OE or reproduction C4 weatherstrip profiles
Installation Notes
Pins install by pressing through the pre-molded holes in the weatherstrip into the factory receivers in the header and pillar. Light pressure seats each pin. Do not force—alignment is key to avoiding damage to the underlying fiberglass frame structure.
Weatherstrip Care Tip
Weatherstrip seals are prone to drying and cracking—especially on older Corvettes. Regular maintenance with non-petroleum dielectric silicone grease keeps rubber seals elastic, prevents sticking, and protects against UV damage and extreme temperatures. Apply a small amount to a soft cloth and wipe over rubber seals monthly. This treatment extends the life of weatherstrips on doors, window seals, sunroofs, trunks, hoods, and convertible tops. Avoid petroleum-based products, which accelerate deterioration and surface cracking.
Because Details Matter
Correct weatherstrip mounting pins eliminate stress points and prevent seal fatigue. Using the proper factory-style retainers ensures your weatherstrip sits flush and performs as GM intended—quiet, watertight, and built to last.
Also known under these part numbers: (For reference only)
- 12503854
- 25016383
- 663001
- 686420318965