Baldwin 18031 Transmission Filter

Baldwin 18031 Transmission Oil Filter

Baldwin 18031 is a transmission oil filter for Buick-built THM350, THM350C, and THM375B rear-wheel-drive 3-speed applications. It includes the furnished pan gasket and is sized for the listed GM fitments, including Pontiac, Buick, Oldsmobile, Cadillac, Chevrolet, and GMC light-duty trucks.

Key Features

• Transmission oil filter for THM350, THM350C, and THM375B transmissions
• Fits 1975-1983 Buick, Oldsmobile, Pontiac, 1980 Cadillac, 1976-1983 Chevrolet automotive applications, and 1977-1980 / 1983 GMC light-duty trucks
• Length: 7 15/32 in. (189.7 mm)
• Width: 7 in. (177.8 mm)
• Furnished gasket included
• Pan gasket included; pan gasket contains 13 bolt holes
• Replaces GMC 8641910 and WIX 51894, 58894

Detailed Description

Baldwin 18031 is built for Buick-built THM350-family automatic transmissions used in a range of GM rear-wheel-drive vehicles. This Baldwin 18031 transmission oil filter matches the listed dimensions and gasket configuration for service work on applications such as the Pontiac Grand LeMans, Pontiac Bonneville, Buick Century, Buick Regal, and Oldsmobile Custom Cruiser. It is also listed for Chevrolet automotive and GMC light-duty truck applications with the same transmission family.

This part cross-references GMC 8641910 and WIX 51894, 58894 for the same application.

What It Helps Address

• Restricted transmission fluid flow caused by a clogged filter
• Contamination in the transmission pan during service
• Fluid pickup issues in THM350, THM350C, and THM375B units
• Maintenance needs during transmission pan removal and fluid service
• Replacement of worn or incorrect filter and gasket components

Installation Notes and Tips

• Verify transmission type before ordering: THM350, THM350C, or THM375B.
• Confirm pan gasket bolt-hole count matches the application; this gasket is noted as 13-bolt-hole.
• Inspect the pan, sealing surfaces, and fluid condition during installation.
• Use the listed dimensions and fitment data to confirm the correct Baldwin 18031 filter for your vehicle.

Quality Assurance

Baldwin manufactures filtration components for automotive service applications with fitment-specific dimensions and OE-style replacement references. Baldwin 18031 is listed with direct replacement references and vehicle-specific fitment data for GM rear-wheel-drive transmissions.