BCBC M255HV-294S Engine Oil Pump

Engine Oil Pump Overview

This Melling engine oil pump is a stock replacement for a wide range of GM trucks, vans, chassis cabs, and Hummer applications. Part number M255HV-294S is built for dependable oil pressure control with high-volume output and improved design details.

Key Features

• High-volume gear pump with standard pressure output
• Steel gears and cast iron housing for durable construction
• Precision-ground end plates for improved wear resistance
• Machined gears built to close tolerances for consistent operation
• Individually tested for pressure and flow under engine-like conditions
• Rust preventative finish for added surface protection

Detailed Description

Melling part number M255HV-294S uses gear and gerotor engineering to deliver efficient oil movement and stable engine pressure. The pump features a cast iron housing and cover, steel gears, a guide, and a pickup screen, with a high-volume design that adds 10 percent over stock. It is a direct-fit style engine oil pump for applications such as Chevrolet C3500HD, GMC Savana 3500, and Hummer H1, as well as other compatible GM platforms listed in the fitment data. Part number M255HV-294S is made in the USA and assembled to production standards focused on consistent pressure and flow.

What It Helps Address

• Low or inconsistent engine oil pressure
• Worn pump components that reduce oil circulation
• Oil delivery issues caused by pump wear or poor flow control
• Pressure loss in high-demand engine applications
• Replacement needs for stock-style GM oil pump service

Installation Notes and Tips

Verify engine application, pickup tube and screen configuration, and pump dimensions before installation. This pump uses a drive shaft design and does not include a gasket or seal, drive shaft, or bolts. The fitment list includes Chevrolet C2500, GMC K3500, and Workhorse P42 applications, so confirm the exact engine setup against the vehicle service information before assembly.

Quality Assurance

Melling states that each pump is manufactured and assembled to high production standards, then individually tested for pressure and flow to simulate real engine operating conditions. The M255HV-294S is made in the USA and built with close-tolerance machining for consistent performance.