Product Description
Keep your VP44-fueled 2nd Gen alive with genuine CUMMINS 3943775 OEM #6 FUEL INJECTION LINE. This is the high-pressure supply tube from the VP44 pump to cylinder #6 on 1998.5–2002 Ram 5.9L ISB 24V trucks and select Stage 2 ISB/QSB 5.9 industrial engines. Precision-formed steel, factory flare angles, and OEM fittings give you leak-free, repeatable torque and long-term durability.
- Direct-fit OE #6 injector line for 1998.5–2002 Ram 5.9L 24V (VP44).
- Genuine Cummins part – not a copy or universal bend.
- Correct routing and length for proper clamp alignment and vibration control.
- Built for high-pressure common VP44 rail pressures and daily diesel abuse.
FITMENT
- Engine: Cummins ISB 5.9L 24V with VP44 injection pump.
- Automotive: 1998.5–2002 Dodge Ram 2500 / 3500, 5.9L 24V Cummins (VP44).
- Position: Cylinder #6 high-pressure fuel injection line (VP44 to injector).
- Industrial / Off-Highway: Used on select Stage 2 ISB/QSB 5.9 applications – always confirm by ESN before ordering.
WHY CHOOSE GENUINE CUMMINS FROM CPP DIESEL?
- OE geometry and flare design to seal correctly on stock injectors and VP44 pump.
- Corrosion-resistant steel line to handle years of heat cycles and vibration.
- Backed by CPP Diesel’s Cummins experts and fast shipping.
INSTALL TIPS
- Always start flare nuts by hand to avoid cross-threading the injector or pump.
- Route line exactly like factory and re-use or replace line clamps and the CUMMINS 3946440 FUEL LINE BRACKET / TUBE BRACE so the tube is fully supported.
- Torque nuts to factory spec from the service manual and re-check for leaks after the first warm-up cycle.
- If one line cracked, closely inspect the remaining #1–#5 lines and clamps for chafe, corrosion, and fatigue.
CROSS-REFERENCE & RELATED CUMMINS PARTS (CPP DIESEL)
Round out your VP44 fuel system refresh with other genuine Cummins parts on CPP Diesel:
- #1 Line: CUMMINS 3943765 OEM FUEL INJECTION LINE – CYLINDER #1
- #2 Line: CUMMINS 3943767 OEM FUEL INJECTION LINE #2
- #3 Line: CUMMINS 3943769 OEM #3 FUEL INJECTION LINE
- #4 Line: CUMMINS 3943771 OEM FUEL INJECTION LINE #4
- #5 Line: CUMMINS 3943773 OEM #5 FUEL INJECTION LINE
- Return Line Tee: CUMMINS 3905353 FUEL RETURN LINE TEE FITTING
- Return Line Grommet Seals (3 required): CUMMINS 3905351 FUEL RETURN LINE GROMMET SEAL
- VP44 Return Line: CUMMINS 3945707 FUEL DRAIN TUBE (VP44 RETURN LINE)
- Head-to-Tee Return Line: CUMMINS 3942966 FUEL RETURN LINE (CYLINDER HEAD TO TEE)
- Return Line to Tank: CUMMINS 3942592 FUEL DRAIN TUBE / RETURN LINE (TO TANK)
WHAT’S IN THE BOX
- (1) Genuine Cummins #6 Fuel Injection Line – Part Number 3943775
FAQ
WILL THIS FIT MY 1998.5–2002 5.9L 24V (VP44) RAM?
Yes. Cummins 3943775 is the OEM #6 cylinder high-pressure fuel line for 1998.5–2002 Ram 2500/3500 trucks with the 5.9L ISB 24-valve engine and VP44 injection pump. Always confirm by VIN/ESN if you suspect parts have been swapped.
IS THIS A GENUINE CUMMINS LINE OR AFTERMARKET?
This listing is for a genuine Cummins injector fuel supply tube with OEM geometry, materials, and flare design – exactly what the engine was designed around from the factory.
DO I NEED TO REPLACE ALL SIX LINES AT THE SAME TIME?
You can replace only the failed #6 line, but many owners choose to replace #1–#6 together if age, corrosion, or vibration damage is visible. At a minimum, inspect the remaining lines, clamps, and the 3946440 tube brace for chafing or cracks.
WHAT TORQUE SPEC SHOULD I USE ON THE FLARE NUTS?
Always follow the factory Cummins / Dodge service manual torque specs for VP44 high-pressure lines. Over-torquing can distort the seats; under-torquing can cause leaks and aeration. After torquing, prime the system and re-check for seepage once the engine is warm.
DOES THIS LINE WORK ON INDUSTRIAL ISB/QSB 5.9 APPLICATIONS?
The 3943775 tube is also used on certain Stage 2 ISB/QSB 5.9 engines, but industrial fitment should always be confirmed by engine serial number (ESN) and parts catalog before ordering.
Specifications for cummins 3943775
| Field | Value |
|---|---|
| Brand | Cummins Genuine OEM |
| Part Number | 3943775 |
| Product Type | Injector Fuel Supply Tube / #6 Fuel Injection Line |
| Engine Platform | Cummins ISB 5.9L 24V, VP44 (automotive); select Stage 2 ISB/QSB 5.9 industrial |
| Automotive Fitment | 1998.5–2002 Dodge Ram 2500/3500 with 5.9L ISB 24V Cummins (VP44) |
| Position | Cylinder #6 high-pressure line (VP44 pump to injector) |
| UPC | Not specified by Cummins (no UPC published in available OEM data) |
| GTIN | Not specified / not published |
| Cross Reference | 3943775, CUM3943775 (distributor/aftermarket catalog references) |
| E-Codes / Emissions Family | Stage 2 ISB/QSB 5.9 applications – verify by engine dataplate/ESN |
| Package Weight | Approx. 0.54 lb (0.24 kg) |
| Package Dimensions | Approx. 21.5 in x 1.0 in x 1.0 in (for boxed tube) |
| Hazard Class | Non-hazardous automotive engine component |
| Shipping Method | Small parcel – ships in a protective tube/box to prevent bending |
| Country of Origin | Typically USA / Mexico for Cummins genuine parts (confirm on box or label) |
| Prop 65 Warning | Yes – Diesel engine components may be subject to California Proposition 65. For more information see www.P65Warnings.ca.gov . |
