Cummins 4939587 — Genuine Engine Oil Pump for B-Series 5.9L

MPN: 4939587  |  Also Known As: lubricating oil pump, lube oil pump  |  Common Cross-Refs (ID): 3937404, 3941742, 3901175, 3906414, 3914006, 3914008, 3918212, 3924720, 3926203, 3930337

Restore factory oil pressure and flow on your B-series build. This genuine Cummins engine oil pump is a direct-fit replacement for 1989–2002 Ram 5.9L (12-valve & 24-valve) and common 4BT/6BT applications. Built to OE specifications for reliability in towing, work, and daily use.

Features & Benefits

• OE pressure & flow to protect bearings, cam, and turbo.
• Direct-fit install for 5.9L 12V (’89–’98) and 24V VP44 (’98.5–’02) engines.
• Gear-type pump design for durable, consistent lubrication.
• Ideal during overhauls or when correcting low hot-idle oil pressure.
• Genuine Cummins quality and materials.

Verified Fitment (Automotive)

Industrial/Off-Highway: Used widely on 4BT 3.9L and 6BT 5.9L B-series engines; Cummins notes usage primarily on BS3 5.9L B engines. Verify by ESN for equipment applications.

Specifications

• Type: Engine lubricating (gear-type) oil pump
• OE Part Number: 4939587
• Common Cross-Refs (ID): 3937404, 3941742, 3901175, 3906414, 3914006, 3914008, 3918212, 3924720, 3926203, 3930337
• Quantity Required: 1 per engine

Often Paired With

• Oil pan gasket & pickup tube seal/O-ring (replace if hardened or damaged)
• Front cover/timing cover gasket set (as needed during service)
• Fresh oil & filter after installation and first heat cycle

What’s In The Box

• (1) Genuine Cummins Engine Oil Pump (4939587)

Installation Tips

• Pre-lube the pump with clean engine oil before installation.
• Inspect pickup tube and screen; replace damaged seals and torque fasteners to spec.
• Prime the system, verify oil pressure on first start, and recheck for leaks after warm-up.

FAQ

WILL THIS FIT MY 1989–2002 5.9L CUMMINS RAM?

Yes—this OE pump covers 5.9L 12-valve and 24-valve VP44 engines from 1989–2002. Confirm by VIN/ESN if unsure.

DOES IT FIT 2003+ 5.9L OR ANY 6.7L?

No—common-rail engines use different pumps and part numbers.

WHAT ARE COMMON CROSS-REFERENCE NUMBERS?

Frequently seen IDs include 3937404, 3941742, 3901175, 3906414, 3914006, 3914008, 3918212, 3924720, 3926203, and 3930337.

HOW DO I KNOW MY OIL PUMP NEEDS REPLACEMENT?

Low hot-idle oil pressure (with correct viscosity), metallic debris, or excessive wear during teardown are common indicators.

IS THIS A GENUINE CUMMINS PART?

Yes—OE Cummins 4939587.