⚠️ Cummins Diesel Misfuel Warning
If gasoline has been added to a Ram 2500/3500 with the 6.7L Cummins turbo diesel:
- Do NOT start the engine
- Do NOT cycle the ignition (fuel pump may prime the common rail)
- Contact a USIFDA certified technician immediately
⚠️ Stellantis / Ram Position
Ram Heavy Duty diesel fuel system service is documented in Stellantis TechAuthority and Mopar service information. Contaminated fuel and use of improper fuel are excluded from warranty. Tank draining and pump access procedures must follow OEM steps—filler neck siphoning is not a documented Ram procedure.
Vehicle Specifications (US)
| Specification | Details |
|---|---|
| Models | Ram 2500 Heavy Duty, Ram 3500 Heavy Duty |
| Primary Diesel Engine | 6.7L Cummins turbo diesel (Bosch high-pressure common rail—consult model year in TechAuthority) |
| Gasoline Engines | 6.4L HEMI V8 (select configurations—confirm fuel door label) |
| DEF (Diesel Exhaust Fluid) | Required on emissions-equipped Cummins models—never add DEF to the fuel tank |
| Fuel Tank Capacity (typical) | ~31 gal main tank (2500); larger optional/aux tanks on HD—consult OEM for exact capacity |
| Fuel Pump Access | Varies by cab/bed/tank configuration—consult TechAuthority for VIN |
Related US model: Ram 1500 offered an optional 3.0L EcoDiesel V6 (2014–2023), also common rail and sensitive to gasoline contamination.
TechAuthority / Mopar Procedure Summary
Fuel Tank Service (typical sequence)
- Release fuel system pressure per service information
- Disconnect negative battery cable
- Drain fuel tank into approved containers
- Support tank; disconnect lines, filler, and vent as required
- Lower tank per Ram HD service manual
USIFDA Recommended Methods
✓ Method A: Fuel Module Access (when documented)
Applicable when OEM allows pump module access without full tank drop and the engine was not run on contaminated fuel.
✓ Method B: Full Tank Drop
Required when the engine was started on contaminated fuel, dual tanks are present, or OEM mandates tank removal for flush.
✗ Filler Neck Extraction
Not Approved as a standalone certified process on Ram HD—follow TechAuthority tank/module procedures.
⚠️ Common Rail Sensitivity
- Gasoline reduces diesel lubricity and can damage high-pressure pump and injectors
- If the engine was run, injector and pump replacement may be required—consult OEM and insurer
- DEF misfuel (DEF into diesel tank) causes separate SCR damage—treat as distinct contamination event
Estimated Labor Time
| Scenario | Typical Hours |
|---|---|
| Drain without engine run (access permitting) | 2 - 4 hours |
| Full HD tank drop and flush | 4 - 8 hours |
| Fuel system component replacement after engine run | 8+ hours |
Need Ram HD Fuel Contamination Service?
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