Pioneer Cables 749090 Automatic Transmission Extension Housing Gasket

Automatic Transmission Extension Housing Gasket

Pioneer Cables 749090 is an automatic transmission extension housing gasket for a wide range of classic GM, Jeep, Jaguar, Rolls-Royce, Buick, Cadillac, Oldsmobile, and Pontiac applications. It is an exact-fit replacement part built for direct service on vehicles that need a precise seal at the transmission extension housing.

• Exact-fit replacement from Pioneer Transmission Components
• Automatic transmission extension housing gasket for sealing service
• Fits many GM truck, van, SUV, and passenger car applications
• Also listed for select Jaguar and Rolls-Royce models
• Cross-references Dorman - HELP 14523 for the same application
• Part number: 749090

Fitment Coverage

• Fits 1987-1990 Cadillac Brougham, N/A
• Fits 1967-1984 Cadillac Fleetwood, N/A
• Fits 1967-1981 Cadillac DeVille, N/A
• Fits 1975-1978 Cadillac Eldorado, N/A
• Fits 1976-1978 Cadillac Seville, N/A
• Fits 1987-1990 Chevrolet Blazer, N/A
• Fits 1975-1990 Chevrolet G10, N/A
• Fits 1975-1990 Chevrolet G20, N/A
• Fits 1975-1990 Chevrolet G30, N/A
• Fits 1988-1990 Chevrolet C1500, N/A
• Fits 1988-1990 Chevrolet C2500, N/A
• Fits 1988-1990 Chevrolet C3500, N/A
• Fits 1975-1986 Chevrolet C10, N/A
• Fits 1975-1986 Chevrolet C20, N/A
• Fits 1975-1986 Chevrolet C30, N/A
• Fits 1975-1986 Chevrolet K10, N/A
• Fits 1975-1986 Chevrolet K20, N/A
• Fits 1977-1986 Chevrolet K30, N/A
• Fits 1977-1986 Chevrolet K5 Blazer, N/A
• Fits 1970-1977 Chevrolet Corvette, N/A
• Fits 1974-1975 Chevrolet Camaro, N/A
• Fits 1975-1975 Chevrolet Malibu, N/A
• Fits 1975-1975 Chevrolet Monte Carlo, N/A
• Fits 1975-1975 Chevrolet Nova, N/A
• Fits 1975-1975 Chevrolet El Camino, N/A
• Fits 1975-1975 Chevrolet Impala, N/A
• Fits 1975-1990 GMC G1500, N/A
• Fits 1975-1990 GMC G2500, N/A
• Fits 1975-1990 GMC G3500, N/A
• Fits 1977-1990 GMC Jimmy, N/A
• Fits 1979-1986 GMC C1500, N/A
• Fits 1979-1986 GMC C2500, N/A
• Fits 1979-1986 GMC C3500, N/A
• Fits 1979-1990 GMC P3500, N/A
• Fits 1987-1990 Jaguar XJ6, N/A
• Fits 1981-1990 Jaguar XJ12, N/A
• Fits 1977-1990 Jaguar XJS, N/A
• Fits 1987-1990 Jaguar Vanden Plas, N/A
• Fits 1986-1990 Rolls-Royce Corniche II, N/A
• Fits 1981-1990 Rolls-Royce Silver Spirit, N/A
• Fits 1981-1990 Rolls-Royce Silver Spur, N/A

Detailed Description

This Pioneer Cables transmission extension housing gasket is made for service work where a clean, accurate seal is needed between the transmission case and extension housing. Pioneer Transmission Components are exact-fit replacement parts, giving technicians and DIY builders a direct replacement option for many older GM rear-wheel-drive platforms as well as select luxury and specialty vehicles. Common search applications include Chevrolet C10 transmission extension housing gasket, GMC Jimmy transmission gasket, and Cadillac Fleetwood automatic transmission gasket.

Part number 749090 also appears in cross-reference listings with Dorman - HELP 14523 for the same application. If you are replacing a leaking extension housing seal on a Chevrolet Corvette, GMC G-series van, or a Jaguar XJS, this gasket is listed for the corresponding transmission service use.

Common Problems This Part Can Address

• Transmission fluid seepage at the extension housing joint
• Wet or stained transmission tailhousing area
• Seal failure after transmission service or disassembly
• Loss of a proper gasket seal during extension housing repair
• Fitment issues when replacing a worn original gasket on older GM, Jeep, Jaguar, or Rolls-Royce applications

Installation Notes and Tips

Clean both mating surfaces thoroughly before installation and remove all old gasket material, sealant residue, and debris. Verify transmission family and application notes before ordering, especially where fitment is limited to THM400, THM350, 3L80, THM425, or THM475/M40 configurations. Confirm the vehicle listing against the transmission in the car or truck before assembly.

Quality Assurance

Pioneer Transmission Components are positioned as exact-fit replacement parts for direct service use. This part number, 749090, is cataloged for broad application coverage across classic GM, Jeep, Jaguar, and Rolls-Royce vehicles, with fitment notes provided for transmission-specific applications.