National 714655 Manual Transmission Input Shaft Seal

Manual Transmission Input Shaft Seal for NP4500

National 714655 is a manual transmission input shaft seal built for applications using the New Process 4500 and 4500HD transmission family. It uses a polyacrylate sealing material with a clockwise-spiral lip design and Redicoat surface treatment to support consistent sealing performance in manual gearbox service.

Use this seal when servicing the transmission on Dodge Ram 1500, Ram 2500, and Ram 3500 models, as well as Chevrolet and GMC trucks and SUVs listed below. The 714655 part number is also a direct reference point for buyers searching by National 714655 or by OE-style transmission oil seal specifications.

Key Features

• Manual transmission input shaft seal / oil seal
• Polyacrylate sealing material for transmission fluid sealing applications
• Clockwise-spiral lip design for controlled sealing contact
• Redicoat treated sealing surface
• Inside diameter: 1.375 in. (34.930 mm)
• Outside diameter: 1.989 in. (50.520 mm)
• Width: 0.252 in. (6.400 mm)
• Housing bore: 1.981 in. (50.320 mm)

Detailed Description

National 714655 is part of the 714000 series and is engineered as a transmission sealing component for manual applications. Its dimensions are specified in inch units, with a 1.375-inch shaft size, 1.989-inch outside diameter, and 0.252-inch width, making it a precise service part for the transmission case and shaft interface. Buyers looking for a manual transmission input shaft seal for Dodge Ram 2500, Chevrolet C3500, or GMC K3500 applications will find this part listed across multiple New Process 4500 and 4500HD fitments.

National has supplied sealing solutions for more than 75 years, and this part reflects that focus on dimensional accuracy and material selection for drivetrain service. This part cross-references BBB Industries 13557 for the same application.

What It Helps Fix

• Transmission fluid leaking from the input shaft area
• Oil seepage around the manual transmission seal bore
• Contamination from worn or hardened sealing lips
• Service issues caused by an incorrect shaft-to-seal fit
• Leak-related clutch or bellhousing contamination

Installation Notes and Tips

Confirm the transmission model before installation; this seal is listed for vehicles using the New Process 4500 and 4500HD transmission family. Verify shaft diameter, housing bore, and seal width against the original part before assembly. Clean the bore and shaft surface thoroughly, and inspect for wear, scoring, or damage that could affect sealing performance. For best results, install the seal squarely to avoid lip distortion.

Fits 1994-2005 Dodge Ram 2500, N/A; Fits 1994-2005 Dodge Ram 3500, N/A; Fits 1994-2004 Dodge Ram 1500, N/A; Fits 1995-1996 Chevrolet Tahoe, N/A; Fits 1991-1995 Chevrolet C1500, N/A; Fits 1991-1995 Chevrolet C2500, N/A; Fits 1992-1995 Chevrolet C3500, N/A; Fits 1991-1995 Chevrolet K1500, N/A; Fits 1991-1995 Chevrolet K2500, N/A; Fits 1991-1995 Chevrolet K3500, N/A; Fits 1991-1995 GMC C1500, N/A; Fits 1991-1995 GMC C2500, N/A; Fits 1991-1995 GMC C3500, N/A; Fits 1991-1995 GMC K1500, N/A; Fits 1991-1995 GMC K2500, N/A; Fits 1991-1995 GMC K3500, N/A; Fits 1991-1995 GMC P3500, N/A; Fits 1992-1995 GMC Yukon, N/A; Fits 1991-1994 Chevrolet Blazer, N/A; Fits 1991-1993 Chevrolet P30, N/A; Fits 1992-1993 Dodge D150, N/A; Fits 1992-1993 Dodge D250, N/A; Fits 1992-1993 Dodge D350, N/A.

Quality Assurance

National positions this seal within its long-running sealing product line, backed by decades of drivetrain and fluid-sealing experience. The 714655 is built to match the listed dimensions and application requirements for manual transmission service.