5.9L Cummins Common Rail Oil Cooler Kit 2003-2007 OEM 3959031 - Cummins

Overview

This is an engine oil cooler / oil-cooler service kit for the Ram, Dodge 5.9L Cummins Common Rail diesel (2003-2007). Built to OEM specification and engineered as a direct-fit replacement for a professional-grade 5.9L Cummins Common Rail repair or service. Every order ships fast and is backed by our support team.

What It Does & How It Helps

The oil cooler is a heat exchanger that sheds heat from the engine oil into the coolant. On the 6.0L Power Stroke it is a known weak point: its narrow passages plug with casting sand and coolant scale, oil temperature climbs, the gap between oil (EOT) and coolant (ECT) temperature grows, and the EGR cooler downstream soon fails too. A new oil cooler — or a full cooler kit with gaskets and O-rings — restores proper oil cooling and protects everything downstream, making it one of the most valuable services you can do on these trucks.

What's Included

• the oil cooler and/or its gaskets and O-rings as specified

Fitment

Fits Ram, Dodge trucks equipped with the 5.9L Cummins Common Rail diesel engine, 2003-2007. Please confirm your engine and year before ordering to ensure correct fitment.

Common Symptoms & When to Use

Consider this 5.9L Cummins Common Rail part when you experience:

• high oil temperature or oil and coolant intermixing
• an EOT-ECT delta fault (6.0 Power Stroke)
• a clogged or leaking oil cooler
• an oil cooler service or replacement

Specifications

• OEM Part Number: 3959031
• Engine: 5.9L Cummins Common Rail
• Year Range: 2003-2007

Quality & Service

Fast shipping on in-stock orders. Free shipping on orders over $70. Backed by Core Diesel Parts — your source for 5.9L Cummins Common Rail diesel parts.