Bearings

What Are Engine Bearings and Why Do They Matter?

Engine bearings are precision-engineered components that sit between rotating or sliding metal surfaces inside an internal combustion engine, creating a thin, oil-lubricated buffer that prevents direct metal-to-metal contact. Without properly functioning bearings, the immense forces and heat generated by a running engine would quickly destroy critical components like the crankshaft, camshaft, and connecting rods. Whether you are performing a routine engine rebuild, repairing worn internals, or assembling a high-performance powerplant, selecting the right bearings is one of the most consequential decisions of the job.

Engine bearings come in several distinct types, each serving a specific role in the valvetrain and bottom end. Engine crankshaft main bearings support the crankshaft as it rotates within the engine block, absorbing the tremendous radial loads generated by combustion. Engine connecting rod bearings fit between the connecting rod journals and the crankshaft, handling the extreme reciprocating forces transferred from the pistons. Engine camshaft bearings allow the camshaft to spin smoothly within its bores while maintaining proper oil film pressure. More specialized applications include engine balance shaft bearings, which reduce vibration in certain engine designs, and engine piston wrist pin bearings, which cushion the connection between the piston pin and the connecting rod small end.

Key Considerations When Shopping for Engine Bearings

Bearing selection is not a one-size-fits-all proposition. Wall thickness, crush height, oil clearance, and material composition all vary by application — and getting these specifications wrong can lead to premature wear, oil starvation, or catastrophic failure. For stock rebuilds, OEM-equivalent bearings restore proper clearances and durability. For high-performance or forced-induction builds, tri-metal or specially coated bearings offer increased load capacity, seizure resistance, and longevity under conditions that would overwhelm standard parts. Always consult engine specifications, measure journals carefully, and match the bearing grade to your application.

Top Engine Bearing Brands

King Engine Bearings has been dedicated exclusively to engine bearings since its founding in 1960. Because engine bearings are their only product, King has developed deep expertise in bearing metallurgy, design, and manufacturing — earning certifications as both a TS16949 automotive and AS9100 aerospace manufacturer. Their line covers OEM replacement and high-performance applications across automotive, truck, marine, and aviation engines.

Clevite traces its roots to 1929 and holds a legendary status in the engine bearing world. Their signature TriMetal™ construction — a steel back, copper-lead alloy substrate, and electroplated surface layer — has been the industry benchmark for performance and racing applications for decades, trusted by NASCAR and Indy Car programs alike.

ACL Bearings is a premier name in motorsports-grade engine bearings. Their Race Series bearings feature tri-metal construction, micron-tolerance machining, and optimized oil clearances, and have been standard equipment in championship-winning engines across NHRA, NASCAR, drift, and land speed racing disciplines.

Dura-Bond is a well-regarded specialist in camshaft bearings and other precision engine components, offering a broad catalog of replacement bearings for domestic and import applications popular with professional engine builders and restoration shops.

Federal Mogul is a globally recognized OEM and aftermarket supplier whose engine bearings are engineered to meet or exceed original equipment specifications, making them a reliable choice for stock replacements across a wide range of domestic and import vehicles.