Are you building your 6.7L Cummins actually to handle power, not just survive at stock levels? The HP Reman Extreme Long Block from D&J Precision Machine is built for trucks that live under load, see heavy tuning, and demand more from their engine every time they’re driven. This isn’t a basic remanufactured replacement; it’s a fully upgraded long block designed to eliminate common weak points and give you a foundation that can take real abuse.

Whether you’re towing heavy, pushing horsepower, or just want a setup you don’t have to second-guess, this engine delivers a noticeable jump in confidence. It’s built to deliver consistent performance under boost, with improved airflow and valvetrain control that keep everything stable. If you’re tired of worrying about reliability once you add power, this is the kind of engine that lets you actually use it.

Each HP Reman Extreme long block starts with a fully disassembled core that’s cleaned, crack-checked, and precision-machined using CNC blueprinting processes to restore and optimize all critical tolerances. The block is bored, honed, and decked, while the rotating assembly is carefully measured and set up to ensure proper clearances for durability and long-term performance.

This package is fully assembled from the oil pan up, delivering a complete, ready-to-install foundation. It typically includes upgraded internal components and airflow improvements designed to handle increased cylinder pressure and sustained boost levels, making it well-suited for towing, tuned applications, and higher-horsepower builds.