7.3 OBS Powerstroke HPX High Pressure Crossover Kit – Strictly Diesel / Driven Diesel DD-73L-HPX-OBS

The Driven Diesel (Strictly Diesel) Stainless Steel High Pressure Crossover (HPX) line connects the driver-side and passenger-side high-pressure oil rails on 1994–1997 7.3L Powerstroke engines. This balances the high-pressure oil system and reduces injection control pressure (ICP) spikes. Most trucks experience smoother operation, and many owners notice quieter engine noise as a result.

Key Features

• High-grade MIL-SPEC stainless steel tubing with aircraft-quality steel fittings
• Pre-bent, pre-assembled line with pre-crimped ferrules for straightforward installation
• Designed for thousands of miles of reliable service
• Same proven design previously sold under the KCM Diesel brand

Fitment

• 1994–1997 Ford 7.3L Powerstroke pickups (OBS)
• Compatible with stock or “drop-in” style turbochargers
• Does not fit trucks with T4-style turbochargers (clearance interference with larger compressor housings)

O-Ring Information

The cylinder head fittings use AS568-905 (also called -905 or #5 boss) O-rings. Nominal size: 0.414″ ID × 0.072″ cross-section, 90 durometer. Viton is strongly preferred for high-temperature engine oil service. These O-rings seal the fittings in the high-pressure oil rail ports in the heads. Do not overtighten the fittings (torque 15–18 ft-lbs max)—the O-ring does the sealing.

What’s Included

• 1 pre-bent stainless steel HPX crossover line
• 2 cylinder head fittings (loosely pre-installed)

This is a popular and well-regarded upgrade for OBS 7.3L trucks looking for more consistent ICP and smoother running characteristics.