Product Description
Genuine Cummins
Cummins 3942966 — Fuel Injector Return Line (Cylinder Head to Tee)
MPN: 3942966 | Also Known As: fuel drain tube, fuel return line | Position: Cylinder head → tee fitting (VP44 systems)
Why This Part
- ✓ OE-formed steel line for correct routing and leak-free sealing.
- ✓ Direct-fit for ’98.5–’02 Ram 5.9L 24V (VP44) return circuit.
- ✓ Restores proper return-to-tank flow from the cylinder head.
- ✓ Genuine Cummins quality and corrosion resistance.
OE Fit Stock Replacement 1 Per Engine
Quick Specs
| Type | Fuel injector return/drain line |
|---|---|
| OE Part # | 3942966 |
| System | VP44 (24-valve) |
| Qty Required | 1 per engine (sold individually) |
Verified Fitment (Automotive)
| Year Range | Engine | Chassis |
|---|---|---|
| 1998.5–2002 | Ram 5.9L ISB 24V (VP44) | Ram 2500/3500 |
Notes: Routes from the back of the cylinder head to the tee fitting in the return circuit. Always confirm by VIN/ESN.
Often Paired With
- Return Line (VP44 → Tee): 3945707
- Return Line Tee Fitting: 3905353
- Alt. Return Line: 3942592 (head/tee variant on some builds)
- Banjo gaskets & small hardware as needed
What’s In The Box
- (1) Genuine Cummins Fuel Return/Drain Line (3942966)
- Includes grommet & nut on many OE kits; hardware availability may vary by supplier.
Install Tips
- Work on a cool engine; relieve fuel system pressure before disconnecting.
- Match bends/orientation to the original; replace aged grommets/seals.
- Prime system and check for leaks after start-up.
FAQ
WILL THIS FIT MY 1998.5–2002 24-VALVE CUMMINS?Yes—designed for the VP44-equipped 5.9L 24V return circuit from the cylinder head to the tee fitting.
WHAT DOES THIS LINE CONNECT?It routes fuel from the back of the cylinder head to the return tee, sending unused fuel back to the tank.
DOES IT INCLUDE A GROMMET AND NUT?Many OE kits include the grommet and nut; if not supplied in your package, reuse or order replacements.
IS THIS A GENUINE CUMMINS PART?Yes—OE Cummins 3942966 for correct fit, material, and routing.
WHAT OTHER LINES GO WITH THIS?Common companions are 3945707 (VP44→tee) and tee fitting 3905353; some builds use 3942592.
Product Videos
Custom Field
Vehicle Year 1998.5,1999,2000,2001,2002
Vehicle Make DODGE
ENGINE 5.9L
