InMotion RB6303-ZZ Manual Transmission Countershaft Bearing - Rear

Manual Transmission Countershaft Bearing Overview

InMotion RB6303-ZZ is a round, single-row ball bearing built for manual transmission countershaft service and other rotating assemblies that need stable, low-friction operation. With a 0.669 in inside diameter, 1.85 in outside diameter, and 0.551 in width, this bearing is sized for precise support in demanding automotive and industrial use.

It is also referenced in applications tied to alternator service on select Chrysler, Dodge, Plymouth, Audi, and Nissan vehicles, including Dodge D100, Dodge Ramcharger, and Chrysler New Yorker platforms. The RB6303-ZZ part number is a useful reference when matching bearing dimensions and application requirements.

Key Features

• Part number: RB6303-ZZ
• Brand: InMotion
• Type: Ball bearing
• Row quantity: 1
• Round bearing design for consistent rotation
• Inside diameter: 0.669 in
• Outside diameter: 1.85 in
• Width: 0.551 in
• Built for smooth operation and reduced friction in rotating components

Detailed Description

The InMotion RB6303-ZZ bearing is a universal-style bearing engineered from high-quality materials for dependable performance in automotive and industrial environments. Its compact dimensions and single-row ball construction support smooth rotational movement, help maintain stability under load, and reduce wear in service areas where precise bearing fit is important. Use RB6303-ZZ when you need a bearing that matches the listed dimensions and application requirements for manual transmission countershaft or related rotating assemblies.

Fitment references include 1980-1982 Nissan 210, rear; 1981-1983 Audi Coupe with 65, 75 Amp alternator; and multiple Chrysler, Dodge, and Plymouth vehicles such as Dodge D100, Dodge Ramcharger, and Chrysler New Yorker with 86, 100, or 114 Amp alternator configurations. This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application.

What It Helps Solve

• Excess friction in a rotating shaft or bearing seat
• Noise caused by worn or rough ball bearings
• Loss of smooth countershaft rotation in manual transmission service
• Dimensional mismatch when replacing a worn bearing by size
• Stability issues in rotating automotive or equipment assemblies

Installation Notes and Tips

Confirm the inside diameter, outside diameter, and width before installation. Match the bearing to the exact application and verify whether the vehicle uses the listed alternator configuration or rear position where applicable. Clean the housing, inspect the shaft or seat for wear, and install the bearing with proper tools to avoid damage to the race or rolling elements. The RB6303-ZZ part number should be checked against the original bearing markings whenever possible.

Quality Assurance

InMotion markets this bearing as a high-quality, multi-purpose component intended for reliable operation across different automotive and industrial environments. Its single-row ball design and dimensional consistency support long service life when installed in the correct application.