P0456 on Your 2018 Ram 1500: Which Generation?
Your 2018 Ram 1500 may be the DS Classic (4th gen) or the all-new DT (5th gen). Both use a Stellantis EVAP system with NVLD. The 5.7L HEMI or 3.6L V6 is unaffected. All basic warranties expired. Federal emissions (8yr/80k) through 2026—last window.
Clues
- Check engine light on
- P0456 stored
- No performance symptoms
- Gas cap shows wear after 7+ years of truck use
Suspects
- Gas Cap Seal (High Likelihood): Seven years of heavy use. $10–$15.
- NVLD Sensor (High Likelihood): Well-documented failure. Under emissions warranty or $130–$300.
- Purge Solenoid Valve (Medium Likelihood): HEMI heat over 7 years. $110–$260.
- EVAP Hose (Medium Likelihood): Under-bed rubber deterioration. $130–$270.
- Charcoal Canister (Low Likelihood): Years of fuel overfilling. $220–$420.
Diagnostic Steps
- Replace gas cap—$10–$15
- Clear code, drive 2–3 cycles
- Check federal emissions warranty—8yr/80k through 2026
- Dealer wiTech if under emissions warranty
- Independent shop smoke test ($80–$150) if expired
Costs
- Gas cap: $10–$15
- NVLD sensor: $130–$300
- Purge valve: $110–$260
- Federal emissions through 2026—last window
Can I Drive?
Yes. P0456 has zero impact on the HEMI, 4x4, towing, or payload.
Warranty
All basic warranties expired. Federal emissions 8yr/80k through 2026—last window. Act now before emissions warranty expires.