If a 1999–2003 Ford 7.3 Powerstroke is leaving oil in the valley, one of the first suspects is the high-pressure oil (HPOP) hose and its STC quick-connect fittings. The upgraded Riffraff HPOP JIC lines replace that stock STC setup with a proven OEM Eaton upgraded hose + JIC adapters—built for a secure, no-leak connection without gambling on off-brand “universal” hoses.

Check Them Out:  

HPOP JIC Line - Passenger Side Head 99-03: https://www.riffraffdiesel.com/hpop-jic-line-passenger-side-head-99-03/

HPOP JIC Line - Driver Side Head 99-03: https://www.riffraffdiesel.com/hpop-jic-line-driver-side-head-99-03/

The problem they solve

Factory HPOP hoses use Eaton STC® quick disconnect fittings, which are convenient… until age and heat cycles turn them into a leak or reliability risk. Riffraff’s JIC conversion replaces the STC connection style with threaded JIC fittings for a more secure seal.

 

 

Hose construction (OEM-grade details):

• Eaton hose made from extruded Teflon® resin
• Stainless steel wire braided body
• Protective fire-retardant silicone outer layer
• Adapters included for the HPOP and the cylinder head

 

Fitment note: Available individually—replace both lines if you want to refresh the system completely (passenger-side is a separate part).

 

Install overview: 

Remove the factory STC hoses using the disconnect tool, remove the STC fittings from the heads and HPOP, remove the two HPOP check springs, install the new head fittings, install the new HPOP fittings with Loctite 680 applied only to the boss threads (O-ring side), route the hoses on the factory path, then torque all connections and leak-check.

Note: Check plate springs under the HPOP outlet fittings must be removed for this conversion.

Torque specs and helpful install details

Head fittings: 30 lb-ft (or fully seated)

HPOP fittings: 25 lb-ft (Loctite on boss threads only; do not apply to flared threads)

Hose end nuts: 20 lb-ft

After install, the truck may start hard/run rough while air purges from the high-pressure oil system—it typically improves after about 75 miles.

Let it idle 5–10 minutes, check for leaks, then drive and re-check.

Recommended parts (to make the job painless)

HPOP Line Disconnect Tool (6595) for STC removal

Loctite 680 for the HPOP outlet fittings 

 

Bottom line: If you’re a 7.3 owner chasing a high-pressure oil leak or replacing aging STC hoses before they strand you, the RDP-HPOP-DRVR Eaton JIC line is a clean, OEM-grade upgrade that prioritizes sealing reliability and serviceability.