Product Description
Genuine Cummins 4935981 #1 fuel injection line (injector fuel supply tube) restores proper rail-to-injector sealing on your 2007.5–2018 6.7L ISB Ram. This OEM high-pressure line is pre-formed to factory specs so it drops into place, cures nuisance fuel leaks, and keeps your common-rail Cummins running clean and quiet.
Built to Cummins engineering standards, this tube is designed for the extreme pressure and vibration found in modern common-rail systems. Whether you are chasing down a persistent fuel smell, replacing injectors, or doing preventative maintenance, using genuine Cummins hardware is the safest way to protect your 6.7L investment.
- Direct-fit OEM #1 cylinder injector fuel supply tube for 6.7L ISB Ram.
- Correct flare geometry and nut profile for long-term leak-free sealing.
- Pre-bent, ready to install – no “tweaking” or guesswork required.
- Compatible with automotive Ram 6.7L and many ISB/QSB 6.7 industrial applications (verify ESN).
Fitment Details
Automotive (Ram Pickup & Chassis Cab)
- 2007.5–2018 Ram 2500 6.7L Cummins ISB (24V common-rail)
- 2007.5–2018 Ram 3500 6.7L Cummins ISB (24V common-rail)
- 2009–2010 Ram 4500 6.7L Cummins ISB (24V common-rail)
- 2009–2010 Ram 5500 6.7L Cummins ISB (24V common-rail)
Industrial / Off-Highway (Reference)
- Used on many EPA13 6.7L ISB/QSB engines – always verify by Cummins ESN before ordering.
Position: Cylinder #1 (front of engine, radiator side).
System: High-pressure common-rail fuel supply line from rail to injector.
Cross-Reference & Companion Parts
This genuine Cummins tube is often serviced together with the other high-pressure lines in the 6.7L set:
- CUMMINS 4935982 OEM FUEL INJECTION LINE (#2 OR #3) – ISB 6.7L (2007.5–2018)
- CUMMINS 4935974 OEM #4/#5 FUEL INJECTION LINE – ISB 6.7L (2007.5–2018)
- CUMMINS 4935976 OEM #6 FUEL INJECTOR LINE – ISB 6.7L (2007.5–2018)
- CUMMINS 3957081 OEM #1 FUEL INJECTION LINE – 5.9L (2003–2007) (for earlier 5.9L trucks)
Additional cross-reference part numbers (for reference only): Mopar 68005435AA, 68005437AA, 68005438AA, 68005336AA; Bosch 0445226044.
What’s Included
- (1) Genuine Cummins #1 cylinder injector fuel supply tube – part number 4935981.
No additional fittings, clips, or seals are included. Reuse good hardware or replace as needed.
Installation Notes
- Work on a clean, cool engine and cap open ports to keep debris out of the fuel system.
- Start the nut threads by hand on both ends of the tube before tightening.
- Torque to the factory spec from your Cummins/Ram service manual – do not overtighten.
- Never use sealant or Teflon tape on high-pressure common-rail fittings.
- After installation, prime the system and check for leaks at idle and under load.
FAQ
WILL THIS CUMMINS 4935981 LINE FIT MY RAM 6.7L?
Yes – this genuine Cummins tube fits most 2007.5–2018 Ram 2500/3500 trucks with the 6.7L ISB, along with many Ram 4500/5500 chassis cabs. Always confirm fitment by VIN or engine serial number (ESN) before ordering.
WHICH CYLINDER DOES THE 4935981 FUEL SUPPLY TUBE SERVE?
Part number 4935981 is the #1 cylinder high-pressure fuel line. On a 6.7L Cummins, cylinder #1 is at the front of the engine on the radiator side.
SHOULD I REPLACE ALL LINES WHEN I REPLACE INJECTORS?
It is strongly recommended to inspect every high-pressure line when injectors are serviced. Any line with damaged flares, nut galling, or signs of leakage should be replaced. Many professional technicians replace the affected line (or the full set) at the same time as injectors to avoid repeat comebacks.
IS THIS A GENUINE CUMMINS PART OR AFTERMARKET?
This is a genuine Cummins OEM injector fuel supply tube, sourced from Cummins and sold by CPP Diesel. It is not an offshore or “will-fit” aftermarket copy.
WHAT ARE THE COMPANION CUMMINS PART NUMBERS BY CYLINDER?
The matching Cummins high-pressure lines for a 6.7L ISB are:
#1: 4935981 (this part)
#2/#3: 4935982
#4/#5: 4935974
#6: 4935976
DOES THIS PART CARRY A PROP 65 WARNING?
Yes. Like many fuel system components, handling and installation can expose you to chemicals (including toluene and benzene) known to the State of California to cause cancer and reproductive harm. For more information, visit www.P65Warnings.ca.gov.
Specifications for cummins 4935981
| Brand | Cummins Genuine |
|---|---|
| Part Number | 4935981 |
| UPC | 5217221728872 |
| GTIN | 5217221728872 |
| Application | 2007.5–2018 Ram 2500/3500/4500/5500 6.7L Cummins ISB; EPA13 6.7L ISB/QSB engines (verify by ESN) |
| Cylinder Position | #1 (front of engine) |
| Material | Formed steel high-pressure fuel tube |
| Shipping Weight | Approx. 0.4 lb |
| Package Dimensions | Approx. 9.35 in x 3.95 in x 1.9 in |
| Shipping Method | Small parcel (standard ground) |
| Cross Reference | Mopar 68005435AA, 68005437AA, 68005438AA, 68005336AA; Bosch 0445226044; companion Cummins lines 4935974, 4935976, 4935982 |
| E-Codes | Not specified |
| Prop 65 Warning | Yes – Cancer and Reproductive Harm – www.P65Warnings.ca.gov |
