Which of the following statements about wheel bearings is true?

• A. Tapered wheel bearings are most commonly used on drive axles.
• B. Ball bearings are preferred for heavy-duty applications.
• C. All wheel bearings require regular lubrication.
• D. Sealed bearings must be replaced completely.

Answer: (A)

Tapered wheel bearings are indeed most commonly used on drive axles because they effectively handle both radial and axial loads, which is necessary for the dynamics of powered wheels. Tapered bearings allow for a greater contact area between the roller and the race, which helps distribute weight more evenly and improve overall stability during operation. This feature makes them particularly suitable for driving applications where torque and load need to be managed effectively.

In contrast, ball bearings, often used in lighter applications, may not provide the same strength and load-carrying capability required for heavier, high-torque scenarios. While regular lubrication is important for maintaining all types of bearings, it is not an absolute requirement for every design, particularly those that are sealed or pre-lubricated. Sealed bearings are designed to keep lubrication contained and can often last for the lifetime of the component without needing replacement of the bearing itself, although the entire unit may need to be replaced if it fails.