The 5.7L Hemi in your 2019 Ram 1500 has developed a troubling tick—one that doesn't fade with warmup and seems to be getting worse. Hemi lifter failure has affected many owners across various model years, and understanding the symptoms helps you catch the problem before it causes expensive secondary damage.
How Hemi Lifters Work
The Hemi uses hydraulic roller lifters that ride on the camshaft lobes and transfer motion to push rods and rocker arms, ultimately opening the valves. These lifters are self-adjusting, using engine oil pressure to maintain proper valve lash. The roller design reduces friction compared to flat-tappet lifters.
On MDS-equipped engines, eight of the sixteen lifters (cylinders 1, 4, 6, and 7) contain solenoid-activated mechanisms that collapse on command, deactivating those cylinders for better fuel economy. These MDS lifters are more complex and have additional failure modes.
Early Warning Signs
A tick or tap that follows engine RPM and doesn't fade when warm is the hallmark symptom. Unlike normal cold-start lifter tick (which resolves within 30-60 seconds), a failing lifter ticks continuously. The sound often localizes to one side of the engine or one specific area.
Misfires may accompany the tick if the lifter isn't maintaining proper valve clearance. Check engine lights with cylinder-specific misfire codes (P0301-P0308) often appear, especially on the affected cylinder.
Rough idle develops as the failing lifter prevents proper valve operation. The affected cylinder doesn't breathe efficiently, reducing its contribution to smooth running.
Reduced power becomes noticeable if multiple lifters are affected or if one cylinder's valves aren't opening fully.
Why Lifters Fail
The internal check valve or roller bearing fails, preventing the lifter from holding pressure or rolling smoothly on the cam lobe. Manufacturing defects, oil starvation, or contamination can initiate failure.
Oil quality and change intervals directly impact lifter life. The Hemi's oiling system, particularly the passages feeding the lifters, can clog with sludge from neglected oil changes. Once starved of lubrication, lifter failure accelerates.
MDS lifter failures often trace to the solenoid mechanism or the collapsing mechanism wearing out. The constant activation and deactivation during MDS operation stresses these components.
Confirming the Diagnosis
Use a mechanic's stethoscope to pinpoint which cylinder is making noise. Place the probe on the valve cover directly above each cylinder and compare sounds. The failed lifter's cylinder will be noticeably louder.
Scan for misfire codes and review misfire counter data. The affected cylinder typically shows elevated misfire counts compared to others.
Oil analysis can reveal metal particles consistent with lifter bearing failure, confirming internal wear.
Repair Options and Costs
Replacing just the failed lifter costs less initially but risks repeat failure if other lifters are similarly worn. Single lifter replacement runs $400-$800 including labor (intake manifold must come off for access).
Most experienced technicians recommend replacing all 16 lifters when one fails. This comprehensive approach costs $2,500-$4,000 but prevents repeat tear-downs. Many shops include camshaft inspection or replacement in this service, as a failed lifter can damage its cam lobe.
For high-mileage engines with other wear, a remanufactured engine might make more financial sense than extensive repairs. Reman long blocks installed cost $4,500-$7,000 but provide fresh components throughout.
An MDS delete replaces the complex MDS lifters with standard non-deactivating lifters, eliminating that failure mode. Combined with a tuner to disable MDS in software, this prevents MDS-related failures going forward. Delete kits with installation run $1,500-$2,500.