Crankshaft Main Bearing Set for Subaru Boxer Engines

Why this part is needed

The crankshaft spins at high speed and needs a precise, low-friction support. This bearing set keeps the crank centered, controls oil clearance, and holds stable oil pressure. Fresh bearings restore quiet operation, protect journals, and extend engine life—vital on turbo and high-mileage Subaru motors.

How it works ️

Each shell sits in the block and cap, forming a smooth half-circle. A pressurized oil film separates steel surfaces, turning metal-to-metal contact into hydrodynamic lubrication. Correct clearances keep the oil wedge strong, reduce heat, and maintain stable crank endplay and alignment.

What happens if damaged ⚠️

Worn or scored bearings cause low oil pressure, start-up rattle, hot idle knock, and metallic glitter in oil. Prolonged use risks spun bearings, seized journals, rod knock, and total bottom-end failure. Replace at rebuild or when clearances are out of spec to prevent costly crank machining.

Tech notes ✅

Measure journals, plastigage clearances, torque caps in sequence, and keep oil passages spotless. Use quality break-in oil and monitor pressure after first start.

Compatibility

• Wrx/Levorg
• Legacy
• Impreza
• Forester
• Exiga
• Wrx