Product Description
Genuine Cummins
Cummins 3926103 — Fuel Injector Return Line (Leak-Off / Overflow)
MPN: 3926103 | Also Known As: injector overflow line, leak-off line, fuel return manifold | Cross-Ref: Mopar 4762042
Why This Part
- ✓ OE hardline assembly routes excess fuel back to the tank.
- ✓ Direct-fit for 1994–1998 Ram 5.9L 12-valve (P7100) applications.
- ✓ Restores reliability—prevents leaks, hard starts, and no-start conditions from cracked lines.
- ✓ Durable steel construction with factory bends and sealing interfaces.
OE Fit Stock Replacement 1 Per Engine
Quick Specs
| Type | Fuel injector return line / leak-off manifold |
|---|---|
| OE Part # | 3926103 (Mopar 4762042) |
| Fuel System | 6BT 12-Valve with P7100 |
| Qty Required | 1 per engine (sold individually) |
Verified Fitment (Automotive)
| Year Range | Engine | Chassis |
|---|---|---|
| 1994–1998 | Ram 5.9L 6BT 12-Valve (P7100) | Ram 2500/3500 |
Industrial/Off-Highway: Also used across select 6B5.9/QSB5.9 applications—verify by ESN before ordering.
Often Paired With
- Return Line Seal: Cummins 4942278 (’94–’98)
- Banjo Bolt: Cummins 3905307 (’89–’98)
- Fresh hose washers & inspection after install
What’s In The Box
- (1) Genuine Cummins Fuel Injector Return Line (3926103)
- Fittings/seals sold separately (see “Often Paired With”).
Install Tips
- Work on a cool engine; clean around connections to avoid contamination.
- Replace seals/banjo hardware; torque to factory spec.
- Prime the system and check for leaks; recheck after first heat cycle.
FAQ
WILL THIS FIT MY 1994–1998 12-VALVE CUMMINS RAM?Yes—3926103 is the OE injector return (leak-off) line for 1994–1998 Ram 5.9L 12-valve with the P7100 pump (verify by VIN/ESN).
DOES THIS INCLUDE THE BANJO BOLT AND SEAL?No—order the banjo bolt (3905307) and seal (4942278) separately if needed.
WHAT SYMPTOMS POINT TO A FAILED RETURN LINE?Fuel smell, wet spots, visible cracks, hard starts, or no-start after sitting are typical signs.
IS THIS A GENUINE CUMMINS PART?Yes—OE Cummins 3926103 with factory geometry and materials.
WILL THIS FIT 24-VALVE OR 6.7L TRUCKS?No—this listing targets the 5.9L 12-valve (’94–’98). Later engines use different assemblies.
Product Videos
Custom Field
Vehicle Year 1994,1995,1996,1997,1998
Vehicle Make DODGE
ENGINE 5.9L
