The 2007 Chrysler 300 is a comfortable highway cruiser with decent bones, but the 2.7L V6 is a notorious oil-sludge engine that grenades itself, and even the better powertrains battle weak transmission coolers and mount failures. The HEMI variants are far more reliable if maintained, but all suffer from front-end component wear and electrical gremlins.
2.7L V6 Engine Sludge and Catastrophic Failure
Common · high severityTypical onset: 80,000-130,000 mi
Symptoms: Low oil pressure warning light, Ticking/knocking from engine on cold start, Oil consumption 1 qt per 1,000 miles or worse, Overheating without coolant loss, Seized engine with oil in the pan
Fix: The 2.7L is an interference engine with tiny oil passages that clog with sludge even with regular oil changes. Once bearing damage starts, you're looking at complete engine replacement or rebuild. Used longblock swap takes 14-18 hours, rebuild 20-25 hours. Many shops won't touch a rebuild on these.
Estimated cost: $3,500-6,500
Transmission Oil Cooler Failure and Contamination
Common · high severityTypical onset: 70,000-110,000 mi
Symptoms: Transmission slipping or delayed engagement, Milky/pink fluid in coolant reservoir, Strawberry milkshake appearance in transmission dipstick, Overheating transmission, No reverse or erratic shifting
Fix: The cooler inside the radiator fails and allows coolant into the ATF, destroying clutch packs and valve body. Requires radiator replacement, transmission flush or rebuild depending on contamination level, and all cooler lines. If caught early, external cooler install and flush runs 4-6 hours. If internal damage occurred, add transmission rebuild at 12-16 hours.
Estimated cost: $800-4,200
Transmission Mount Collapse
Common · medium severityTypical onset: 60,000-100,000 mi
Symptoms: Clunk when shifting from Park to Drive or Reverse, Vibration at idle in Drive, Visible engine movement when revving in Park, Excessive driveline lash on acceleration
Fix: The rear transmission mount is hydraulic-filled and collapses internally, allowing excessive powertrain movement. Replacement requires lifting the transmission slightly. Takes 2-3 hours with proper equipment. OEM or quality aftermarket only—cheap mounts fail in 20,000 miles.
Estimated cost: $250-450
Lower Ball Joint and Control Arm Failure
Common · high severityTypical onset: 80,000-120,000 mi
Symptoms: Clunking over bumps from front end, Wandering steering or pulling, Uneven tire wear on inside edge, Failed state inspection for play in ball joint, Catastrophic separation (rare but documented)
Fix: The lower control arms have pressed-in ball joints that wear and develop play. Many shops replace the entire control arm assembly rather than press new joints. Alignment required after. Both sides typically need replacement simultaneously. 3-4 hours labor for both sides plus alignment.
Estimated cost: $600-1,000
TIPM (Totally Integrated Power Module) Failure
Occasional · medium severitySymptoms: Fuel pump not priming (no start), Wipers running on their own, Horn honking randomly, Windows operating by themselves, Multiple warning lights with no stored codes, Stalling while driving
Fix: The TIPM is Chrysler's electronic fuse box/relay center and it fails internally due to corrosion or bad solder joints. Some symptoms are fixed by updated software, others need full TIPM replacement and programming. Replacement takes 2-3 hours. Used TIPMs must be programmed to the VIN. Aftermarket repair services exist for $300-400 but success varies.
Estimated cost: $800-1,400
3.5L V6 Head Gasket Failure
Occasional · high severityTypical onset: 100,000-150,000 mi
Symptoms: White smoke from exhaust on startup, Coolant loss with no visible leaks, Overheating under load, Oil cap shows milky residue, Rough idle and misfires
Fix: The 3.5L can blow head gaskets between cylinders or into coolant passages. Both heads typically need machining or replacement. Job requires removing intake manifold, exhaust, timing components. 12-16 hours labor. Often find warped heads requiring replacement, adding cost.
Estimated cost: $2,200-3,800
Evaporative Emissions System Leaks (EVAP)
Common · low severityTypical onset: 60,000-120,000 mi
Symptoms: Check engine light with P0456 or P0442 code, Fuel smell near filler area, Failed emissions test, Hissing sound when removing fuel cap
Fix: The fuel filler neck, EVAP canister, purge valve, or vent valve develop leaks. Most commonly it's cracked vent lines or a faulty purge valve. Smoke test diagnosis takes 1 hour, repair varies by location. Fuel tank drop required for some components adds 2-3 hours.
Estimated cost: $150-650
Buy a HEMI variant with service records or avoid entirely—the V6 models are ticking time bombs, but a well-maintained 5.7L can be a solid highway cruiser if you accept the suspension and electrical quirks.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.