Product Description
CUMMINS 3943771 OEM FUEL INJECTION LINE #4 – RAM 5.9L (1998.5–2002)
Genuine Cummins high-pressure fuel injection line for cylinder #4 on VP44-equipped 5.9L 24-valve engines. This OE-formed hard line restores precise fuel delivery and leak-free sealing on 1998.5–2002 Dodge Ram 2500/3500 trucks running the 5.9L ISB 24V Cummins.
Features & Benefits
- OE Cummins part 3943771 with factory-correct bends, flare geometry, and fittings for cylinder #4.
- Direct-fit replacement for VP44 high-pressure hard line – no cutting, bending, or adapting required.
- Engineered to handle high injection pressures, heat cycles, and vibration without premature cracking.
- Helps eliminate fuel leaks, aeration, and hard-start issues caused by fatigued or damaged lines.
- Compatible with automotive Ram applications and many Stage 2 ISB / QSB 5.9 industrial engines (verify by ESN).
Fitment
- Engine: 5.9L ISB 24V Cummins with VP44 injection pump.
- Cylinder Position: #4 high-pressure injection line (pump to injector).
- Automotive: 1998.5–2002 Dodge Ram 2500 & 3500, 5.9L 24-valve Cummins (VP44).
- Industrial / Off-Highway: Common on Stage 2 ISB / QSB 5.9 applications – always confirm by Engine Serial Number (ESN).
- Notes: Each cylinder uses a unique pre-bent line. This part number is for cylinder #4 only.
Cross-Reference & Related Cummins Parts (Ram 5.9L 24V VP44, 1998.5–2002)
- #1 Injector Line – CUMMINS 3943765 OEM FUEL INJECTION LINE – CYLINDER #1 – RAM 5.9L 24V (1998.5–2002)
- #2 Injector Line – CUMMINS 3943767 OEM FUEL INJECTION LINE #2 – RAM 5.9L 24V (1998.5–2002)
- #3 Injector Line – CUMMINS 3943769 OEM #3 FUEL INJECTION LINE – RAM 5.9L (1998.5–2002)
- #5 Injector Line – CUMMINS 3943773 OEM #5 FUEL INJECTION LINE – RAM 5.9L 24V (1998.5–2002)
- #6 Injector Line – CUMMINS 3943775 OEM #6 FUEL INJECTION LINE – RAM 5.9L (1998.5–2002) VP44
- Alternative listing (same part) – CUMMINS 3943771 GENUINE OEM INJECTOR FUEL SUPPLY TUBE FOR 1998.5–2002 DODGE RAM DIESEL
Installation Notes
- Work on a cool engine and relieve fuel system pressure before loosening any lines.
- Route the new line exactly like the original; do not attempt to re-bend or twist the tube.
- Start all flare nuts by hand to avoid cross-threading, then torque to factory spec per Cummins service manual.
- Keep all connections surgically clean – cap open ports to keep debris out of the fuel system.
- After installation, prime the system and inspect for leaks at idle and again after warm-up.
Specifications for cummins 3943771
| Brand | Cummins (Genuine OEM) |
|---|---|
| Part Number | 3943771 |
| UPC | Not specified by manufacturer |
| GTIN | Not specified by manufacturer |
| Engine | 5.9L ISB 24V Cummins with VP44 injection pump |
| Application | 1998.5–2002 Dodge Ram 2500/3500 5.9L Cummins; select Stage 2 ISB/QSB 5.9 industrial engines (verify by ESN) |
| Cylinder Position | #4 high-pressure injection line (pump to injector) |
| Shipping Info | Free ground shipping in the continental U.S.; approximate package size 2.5" x 1.0" x 11.5"; ship weight ~0.5–1.0 lb. |
| Cross Reference | Cummins 3943765 (#1), 3943767 (#2), 3943769 (#3), 3943773 (#5), 3943775 (#6) |
| E-Codes | Not specified |
| Prop 65 | WARNING: Cancer and Reproductive Harm – see P65Warnings.ca.gov. |
FAQ
WILL THIS FIT MY 1998.5–2002 5.9L 24-VALVE RAM?
Yes. Cummins 3943771 is the OE high-pressure fuel injection line for cylinder #4 on 1998.5–2002 Dodge Ram 2500/3500 trucks equipped with the 5.9L ISB 24V Cummins and VP44 injection pump. Always confirm by VIN/ESN if components have been changed.
WHICH CYLINDER DOES PART NUMBER 3943771 SERVE?
This line is dedicated to cylinder #4. Each cylinder uses its own unique, pre-bent hard line – do not swap positions between cylinders.
CAN I REPLACE JUST THE #4 LINE OR SHOULD I DO ALL SIX?
You can replace only the failed #4 line, but it’s smart to inspect all six lines and the line clamps for corrosion, rubbing, or fatigue. If several lines show wear, consider replacing the full set (#1–#6) to prevent future leaks.
IS THIS A GENUINE CUMMINS PART OR AFTERMARKET?
This is a genuine Cummins OEM component with factory-correct tube forming and flare geometry. It is not a generic aftermarket substitute.
DO I NEED TO RE-BEND OR MODIFY THIS LINE FOR INSTALLATION?
No. The line is pre-bent to OE geometry. Do not re-bend or kink the tube – misalignment can lead to stress fractures, poor sealing, and repeat failures. If it doesn’t line up, double-check routing and engine configuration.
