Chrysler 300C
5.7L Hemi V8, cast iron block, pushrod two-valve — 375 hp and that unmistakable idle burble. MDS deactivates cylinders 1, 4, 6, 7 under light throttle — deactivated lifters run dry on cam lobes, metal debris destroys the camshaft. Class action: Petro v. FCA. Manual cars skip MDS entirely — no deactivation hardware, no lifter lottery. That is THE buying tip. Software delete via DiabloSport/HP Tuners: $400-650, prevents activation but lifters stay, voids warranty, costs 2-4 MPG. On 0W-40 at 5,000 mile intervals, the bottom end is solid.
Hemi sedan, second generation
360 hp, ZF 8-speed replacing the old 5-speed — noticeably more dynamic than the LX. MDS lifter risk remains. Low-mileage used examples with documented maintenance are solid buys.
Engine Weaknesses 4
MDS deactivates 4 cylinders under light load. Deactivated lifter rollers run dry, metal debris destroys camshaft. Class action: Petro v. FCA (1:22-cv-00621). Engine replacement ~$5,000. Manual cars have NO MDS — this failure doesn't apply to stick-shift Challengers.
Symptoms: Loud ticking progressing to knocking, misfires, check engine light, metal shavings in oil
Plastic impeller separates or bearing wears. Weep hole dripping coolant is the early warning. Bearing failure causes pulley wobble.
Symptoms: Coolant puddle under front, squealing noise, overheating, pulley wobble
Metallic ticking from valvetrain on cold start. Can be harmless exhaust manifold leak or dangerous MDS lifter damage. Tick that persists past warmup is a red flag for lifter failure.
Symptoms: Ticking on cold start, may disappear after warmup (exhaust) or persist and worsen (lifter)
Steel bolts on aluminum heads — different thermal expansion snaps bolts after heat cycles. Ticking on cold start that disappears when metal expands is the classic symptom.
Symptoms: Metallic ticking on cold start, disappears after warmup, exhaust smell in cabin
Vehicle Weaknesses 5
Totally Integrated Power Module controls all electrical functions. Relay failures cause: fuel pump runs continuously, horn sounds randomly, vehicle won't start. Repair service $200-350, new module up to $1,000.
Heater core leaks coolant into the cabin. Sweet smell, greasy film on inside of windshield. Very labor-intensive replacement — full dashboard removal required, 8-12 labor hours.
NHTSA recall for 133 model year 2023 Chrysler 300 vehicles with improperly adjusted parking brake from factory. Vehicle may roll away. Dealer adjusts parking brake free of charge.
Window regulator cable snaps, window drops into door or won't move. 91 reported cases on RepairPal. Affects all years and all doors.
Small plastic gears inside the blend door actuator strip out. Persistent clicking or ticking after startup or temperature change. Dashboard removal required for proper repair.
