The 2017 Chrysler 300 rides on the aging LX platform with generally reliable Pentastar V6 or Hemi V8 powertrains, but transmission cooler failures and expensive lifter/cam issues on the Hemi engines are the major trouble spots that can sideline these cars.
Transmission Oil Cooler Failure
Common · high severityTypical onset: 60,000-100,000 mi
Symptoms: Pink milkshake fluid in transmission pan (coolant mixing with ATF), Transmission slipping or delayed engagement, Engine overheating or transmission overheating warnings, Abrupt failure after coolant enters transmission
Fix: Replace external transmission cooler and flush both cooling system and transmission. If contamination has occurred, transmission rebuild or replacement is often required. Cooler replacement alone: 2-3 hours labor. With transmission damage: 8-12 hours plus rebuild/replacement.
Estimated cost: $600-1,200 (cooler only), $3,500-5,500 (with transmission work)
5.7L Hemi Lifter and Camshaft Failure
Occasional · high severityTypical onset: 80,000-150,000 mi
Symptoms: Ticking or tapping noise from engine, especially on cold start, Check engine light with misfire codes (P0300-P0308), Loss of power and rough idle, Metal shavings in oil from disintegrating lifter rollers
Fix: Replace all 16 lifters, both camshafts, and often pushrods. Requires cylinder head removal. 12-16 hours labor. MDS (cylinder deactivation) lifters fail most often. Oil flow issues and poor maintenance accelerate this.
Estimated cost: $4,000-6,500
Pentastar 3.6L V6 Head Gasket and Coolant Leaks
Occasional · medium severityTypical onset: 100,000-140,000 mi
Symptoms: External coolant seepage from cylinder head mating surface, Overheating under load or at idle, White smoke from exhaust (if internal leak), Oil contamination with coolant (coffee-colored oil)
Fix: Replace both head gaskets, resurface heads if warped. 10-14 hours labor. This generation Pentastar has revised gaskets that address earlier leaking issues, but still occurs with age and overheating events.
Estimated cost: $2,800-4,200
ZF 8-Speed Transmission Output Shaft Bearing
Occasional · medium severityTypical onset: 70,000-120,000 mi
Symptoms: Whining or grinding noise from transmission in all gears, Noise increases with vehicle speed, not engine RPM, Metal debris in transmission pan during service, Eventually leads to complete transmission failure if ignored
Fix: Transmission must be removed, disassembled, output shaft bearing and related components replaced. 8-10 hours labor. ZF 8HP transmissions are generally solid, but this bearing can fail prematurely from lack of fluid changes or manufacturing tolerance issues.
Estimated cost: $2,500-3,800
Transmission Mount Failure
Common · low severityTypical onset: 60,000-90,000 mi
Symptoms: Clunking when shifting from Park to Drive or Reverse, Excessive vibration at idle in gear, Visible transmission sag or torn rubber in mount, Harsh engagement into gear
Fix: Replace transmission mount. 1.5-2 hours labor. The rear transmission mount wears from the weight of the ZF 8-speed and engine torque, especially on the Hemi cars.
Estimated cost: $250-450
Electrical Wiring Harness Corrosion (Recall-Related)
Rare · high severitySymptoms: Intermittent no-start condition, Multiple electrical system warning lights, Loss of power steering assist, Stalling while driving
Fix: Specific to recall for wiring harness contamination near battery. Dealer replaces affected harness sections. 2-4 hours labor. Check if recall 23V-490 was completed.
Estimated cost: $0 (recall coverage)
Buy the V6 if you want reliability and change the transmission fluid religiously; avoid high-mileage Hemis unless lifter/cam work is documented — otherwise budget $5K for eventual engine work.
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.