The 2011 Chrysler 300 SRT8 with the 6.1L HEMI is a potent muscle sedan, but the NAG1 (W5A580) five-speed automatic transmission is its Achilles' heel. Expect transmission-related issues to dominate your ownership experience, especially beyond 80,000 miles.
NAG1 Transmission Solenoid Pack Failure
Common · high severityTypical onset: 70,000-120,000 mi
Symptoms: Harsh or delayed shifts, especially 2-3 and 3-4, Limp mode with P0750-P0758 codes (shift solenoid performance), Slipping between gears or failure to engage certain gears, Check engine light with transmission fault codes
Fix: Requires dropping the transmission pan, replacing solenoid pack and valve body gaskets, fluid and filter change. 4-6 hours labor. Some shops replace entire valve body assembly for longevity.
Estimated cost: $800-1,800
Transmission Control Module (TCM) Corruption
Occasional · high severityTypical onset: 80,000-140,000 mi
Symptoms: Transmission stuck in second gear (limp mode), No communication with scanner in transmission module, Random no-start conditions, Erratic shifting patterns that don't match solenoid codes
Fix: TCM replacement requires programming/flashing to VIN. Module is internal to transmission on NAG1, so pan-drop required. 3-4 hours labor plus dealer programming.
Estimated cost: $1,200-2,200
Transmission Oil Cooler and Line Leaks
Common · medium severityTypical onset: 60,000-100,000 mi
Symptoms: ATF puddles under engine bay, driver's side, Low transmission fluid warnings, Burnt ATF smell, Transmission overheating, especially in summer or towing
Fix: Steel cooler lines rust through at fittings and bends. External cooler can crack. Replace lines as a set, inspect cooler. 2-3 hours labor. Flush system afterward.
Estimated cost: $600-1,200
Transmission Range Sensor (PRNDL) Failure
Occasional · medium severityTypical onset: 90,000-150,000 mi
Symptoms: Dash gear indicator shows wrong gear or blank, Won't start in Park (thinks it's in gear), Reverse lights don't work or stay on, P0705 or P0706 codes (transmission range sensor circuit)
Fix: Sensor is external on driver's side of transmission. Replace sensor and adjust/relearn. 1.5-2 hours labor.
Estimated cost: $300-600
Engine/Transmission Mount Failure
Common · low severityTypical onset: 70,000-110,000 mi
Symptoms: Clunking on hard acceleration or deceleration, Excessive driveline vibration at idle in Drive, Visible powertrain movement when revving in Park, Shifter feels notchy or binds
Fix: Rear transmission mount commonly tears due to HEMI torque. Front engine mounts also fail. Replace mounts, 2-3 hours labor for both.
Estimated cost: $400-800
Fuel System Evaporative Leak (ESIM Module)
Occasional · low severitySymptoms: P0456 or P0442 codes (small EVAP leak), Check engine light, no drivability issues, Fails emissions testing in strict states, Fuel smell near rear of vehicle occasionally
Fix: ESIM (leak detection pump) module on top of fuel tank fails. Tank must be dropped. Common on all LX/LC platforms. 3-4 hours labor.
Estimated cost: $600-1,000
Rear Differential Fluid Leak and Noise
Occasional · medium severityTypical onset: 80,000-130,000 mi
Symptoms: Whining or howling from rear on deceleration, Gear oil drips from pinion seal or cover gasket, Clunking on tight turns (limited-slip clutches worn), Vibration at highway speeds if bearings are failing
Fix: Pinion seal replacement common, 2 hours. If bearings are damaged, full diff rebuild or replacement needed, 6-8 hours.
Estimated cost: $400-2,500
Buy one if you want a V8 thrill and can wrench or budget for transmission work, but skip it if you need appliance-grade reliability — the NAG1 will humble you.
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.