CUMMINS 4988809 OEM #3 FUEL INJECTION LINE (INJECTOR FUEL SUPPLY TUBE) – RAM 5.9L (2003–2007)

Product Description

CUMMINS 4988809 OEM #3 FUEL INJECTION LINE – INJECTOR FUEL SUPPLY TUBE

This is the genuine Cummins 4988809 high-pressure fuel injection line — the #3 injector fuel supply tube — engineered for 2003-2007 Dodge Ram 2500 / Dodge Ram 3500 5.9L ISB 24-valve common-rail engines. This direct-fit OEM part restores proper rail-to-injector fuel delivery, factory-correct geometry, and sealing surfaces — critical to avoid leaks, pressure loss, or injector mis-delivery. Ideal for replacing cracked, fatigued, or leaking lines due to vibration, thermal cycles, or age. 

Fitment & Application

• Year: 2003, 2004, 2005, 2006, 2007
• Engine: 5.9 L ISB / QSB 24-valve common-rail diesel
• Vehicle: Dodge/Ram 2500, 3500 (verify ESN / VIN for common-rail 5.9 engines) 
• Cylinder: #3 (injector line #3) — one per engine, sold individually 

Why This Part Matters

• ✅ OEM-grade material assures durability and reliable sealing under high pressure. 
• ✅ Factory geometry ensures correct injector alignment and consistent fuel delivery. 
• ✅ Prevents leaks, injector timing issues, or poor combustion that can arise from cracked/fatigued tubing. 

Cross Reference / Related Injector Lines

If you need other cylinders, commonly paired OEM lines for 03–07 5.9L: CUMMINS 3957081 #1 Fuel Injection Line, CUMMINS 4988810 #2 Fuel Injection Line, CUMMINS 5289447 #4 Fuel Injection Line, CUMMINS 4988807 #5 Fuel Injection Line, CUMMINS 4988806 #6 Fuel Injection Line. 

Installation & Service Notes

When replacing this line, always ensure the fuel system is depressurized first. Maintain absolute cleanliness — do not kink or pre-stress the line. Start fittings by hand to avoid cross-threading, torque to factory spec, then prime and check thoroughly for leaks. Re-check after initial heat-up cycle.  It’s best practice to replace connector tube seals/washers whenever these lines are disturbed to guarantee leak-free operation. 

FAQ

WILL THIS FIT MY 2003–2007 RAM 5.9L CUMMINS? Yes — this is the OE high-pressure supply line for cylinder #3 on 2003–2007 5.9L ISB common-rail engines (verify by ESN/VIN). 

WHAT CYLINDER DOES 4988809 SERVE? This part is specifically the #3 cylinder injector fuel supply tube. 

IS THIS A GENUINE CUMMINS PART? Yes — this is a genuine OEM Cummins part for proper fitment, materials, and sealing integrity. 

DO I NEED NEW SEALS WHEN I REPLACE THE LINE? It’s strongly recommended to replace injector connector tube seals/washers whenever any injector supply line is removed to ensure proper sealing and prevent leaks.