2019-2024 Ram 6.7L Cummins Fuel Lines

Fuel lines on the 2019-2024 Ram 6.7L Cummins

The 6.7L Cummins fuel system has two sides. The supply side runs from the electric in-tank lift pump, through the frame-mounted water separator and the engine-mounted filter, to the high-pressure pump. The high-pressure side runs from that pump to the common rail and out to the injectors, at up to 29,000 psi on 2019-2024 trucks, compared with 26,000 psi on 2007-2018 trucks. Rail pressure is set by the pump's fuel control actuator. The pump itself is a CP4.2 on 2019-2020 trucks and a CP3 on 2021-2024 trucks. Every line and fitting on the high-pressure side lives at that pressure, so thread size, seat and condition all matter.

What fails and why

Two problems show up in the records for this generation. First, recall 19V-498 covers 2019 Ram 2500, 3500 and cab chassis diesels whose fuel lines may leak fuel into the engine compartment. A fuel smell or a visible leak is the sign, and recall status is tied to your VIN. Second, the CP4.2 on 2019-2020 trucks can fail and shed metal into the rail, injectors, lines and tank. Because that metal lodges in the lines, the factory procedure after a CP4 failure replaces lines and rails along with the injectors. Symptoms of a pump failure include ticking, loss of power, stalling, a no-start, and metal in the fuel filter.

Stock replacement vs. upgrade

If you are repairing after a pump failure, plan on new high-pressure lines to follow the factory approach. If you are working on the supply side, the AN fittings here let you plumb an AN supply line into the CP3 inlet, which pairs with the frame-mounted lift pump and filtration systems sold for 2019-2024 Ram 6.7L trucks. Those systems are built to steady supply pressure and remove water and air before fuel reaches the pump. Larger-bore injection lines, like the oversized lines from Dynomite Diesel, are for owners building a fuel system beyond stock.

What we carry

Exergy Performance supplies the fittings: the 1-018-148 M12x1.5 to -6AN and 1-018-149 M12x1.5 to -8AN high-flow CP3 supply fittings, the 1-008-003 M14x1.5 three-way T fitting, and the 1-018-043 M14x1.5 plug and nut used as a rail cap. Dynomite Diesel Products supplies universal high-pressure oversized injection lines, sold in multiple lengths. For rails, sensors and injectors, see the other fuel system collections for your truck.

Fitment notes

The CP3 supply fittings belong on a CP3. That means every 2021-2024 truck, and a 2019-2020 truck only if it has had the Y78 recall that replaced the CP4.2 with a CP3. Pump parts and fuel-system kits must match the pump that is actually on the truck, so check before ordering. Match thread sizes exactly; the titles call out M12x1.5 and M14x1.5. The Dynomite lines are universal and come in multiple lengths, so measure your run before you order. On a 2019 truck with a leaking line, check recall 19V-498 by VIN before paying for the repair yourself. Verify by VIN.

Frequently asked questions

Is my 2019 Ram covered by the fuel line recall?

Recall 19V-498 covers 2019 Ram 2500, 3500 and cab chassis diesels whose fuel lines may leak fuel into the engine compartment. Have a Ram dealer check your VIN to see whether it applies and whether it has been done. A fuel smell or a visible leak around the lines is the warning sign.

Do I need new fuel lines after a CP4 failure?

The factory procedure says yes. Metal from a failed CP4.2 lodges in the lines and rails, so they are replaced along with the injectors. Left in place, that debris sits upstream of the new injectors.

Will the Exergy CP3 supply fittings fit my 2019-2020 truck?

Only if the truck now has a CP3. 2019-2020 trucks were built with the CP4.2, and the Y78 recall replaced it with a CP3. Confirm which pump is on your truck, since parts must match the pump actually installed.

Not sure what fits? Call the shop at the number in the header, or use the fitment checker on any product page. We install everything we sell.