The NOS Genuine ACDelco GM 1243402 Automatic Transmission Extension Housing Oil Seal is an original equipment replacement designed to prevent transmission fluid leaks at the rear output shaft where the driveshaft slip yoke enters the transmission extension housing. Engineered to General Motors' exact specifications, this OEM seal provides reliable fluid retention, helping maintain proper transmission lubrication and performance. It is also identified as an Automatic Transmission Rear Output Shaft Seal or Extension Housing Oil Seal.
Manufactured from high-quality sealing material, the 1243402 seal is built to withstand transmission fluid, heat, and continuous drivetrain operation. Its precision-molded design ensures a tight, dependable seal while helping protect the transmission from fluid loss and contamination. As a direct OEM replacement, it installs without modification in compatible GM applications.
This New Old Stock (NOS) Genuine ACDelco part fits a wide range of classic 1955–1977 Chevrolet, Buick, and Pontiac vehicles with compatible automatic transmissions. Always verify compatibility using your vehicle's VIN, transmission model, or original part number before purchasing.
Key Features
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Premium Sealing Material: Resists heat, transmission fluid, and normal wear.
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Direct OEM Replacement: Installs without modification on compatible applications.
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New Old Stock (NOS): Genuine unused OEM component for restoration or repair.
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Precision OEM Fit: Ensures dependable sealing and factory-quality performance.
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Genuine ACDelco GM OEM Part: Manufactured to original General Motors specifications.
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Protects Transmission: Helps maintain proper fluid levels and reduce contamination.
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Transmission Extension Housing Seal: Helps prevent transmission fluid leaks at the rear output shaft.
Specifications
- Part Number: 1243402
- Brand: ACDelco / General Motors (GM)
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Fitment Type: Direct OEM Replacement
- Seal Location: Rear Output Shaft / Extension Housing
- Product Type: Automatic Transmission Extension Housing Oil Seal