Quick answer: Radiator Replacement on a 2005–2010 Chrysler 300 is rated Moderate and takes about 2-3 hours. You'll need 12 tools for this job, and parts cost about $265. This guide walks you through the full job step by step, including the mistakes to avoid.
| Part Name |
Part Number |
Price |
Buy |
| Radiator Assembly |
TRQ RDA82685 |
$154.95 |
|
| Radiator Fan Assembly |
TRQ RFA80407 |
$109.95 |
|
| Anti-seize compound |
— |
— |
|
| HOAT coolant |
— |
— |
|
About prices: shown prices are typical retail averages and change frequently; cheaper alternatives may be available. Confirm the current price before buying.
💡 Pro tip: Order all parts at once to save on shipping
Step-by-Step Instructions
Follow these steps carefully
1
Cool down and drain the coolant
The 2005–2010 Chrysler 300 uses HOAT (Hybrid OAT) coolant — NOT the later Mopar OAT. This is orange/pink, 5-year/100,000-mile, part 68051212AB. The switch to OAT (10-year/150k) happened around 2013 — your 300 predates it. Do NOT use OAT in this car without a complete flush, and do NOT mix HOAT with OAT or green coolant — it causes sludge. This is critical: the 300 is the same Chrysler family as the Durango/Grand Cherokee/Cherokee in this group, but from a different coolant era. If converting to OAT, the system must be THOROUGHLY flushed with distilled water first. The 300 is the oldest vehicle in the group (2005–2010) — expect corrosion and seized fasteners. Let the engine cool completely. The 300 has a traditional radiator cap (unlike the newer pressurized-bottle Jeeps).
🔧 Mechanic's note — Tom Becker
Hit those bolts with penetrating oil the night before you touch them. I've snapped enough rusted studs to learn that lesson for you.
2
Remove shrouds, fans, and hoses
Disconnect the negative battery terminal. Remove the fan/shroud assembly. Disconnect transmission cooler lines with line wrenches and plug them. Remove the upper and lower hoses — on a 2005-2010 vehicle, these may be stuck; twist carefully, don't yank.
3
Unbolt mounts and lift out the radiator
Unbolt the radiator mounts. On a 15+ year old 300, these bolts may be severely corroded — apply penetrating oil and work carefully to avoid snapping them. Lift the radiator out, being careful with the A/C condenser. The 300's radiator is a standard RWD design. Note the rubber isolators (they may be deteriorated — consider replacing). Set the old radiator aside. Inspect the thermostat housing for leaks while the system is drained — housing leaks are common on the 300 (195°F thermostat).
4
Transfer parts to the new radiator
Transfer the rubber isolators (or replace if deteriorated) to the new radiator. Compare the new radiator to the old — verify dimensions, hose connections, and transmission cooler fittings.
🔧 Mechanic's note — Tom Becker
I've found that lay the old and new parts side by side before you install anything. Wrong parts in the right box happen more than you'd think.
5
Install the new radiator
Lower the new radiator into position. Reinstall the mounts (use anti-seize on the bolts given the corrosion). Reconnect the transmission cooler lines. Reinstall the fan/shroud assembly. Reconnect the battery. If you replaced the thermostat, ensure the housing is properly sealed.
6
Refill, bleed, and leak-check
Fill with HOAT coolant (68051212AB) — orange/pink, not the purple OAT. Bleed via the air bleeder: run the engine to operating temperature, then loosen the bleeder screw to let air escape until only a steady stream of coolant runs out. Don't open it too far — coolant can spray onto the serpentine belt. Watch your hands for steam. Keep an eye on the reservoir level and top up. If the screw-in bleeder seeps, use Teflon tape. Run with the heater on max. Check transmission fluid. Inspect for leaks at the petcock, hoses, and thermostat housing. The 300's HOAT system is 5-year/100k — mark your calendar. Recheck when cold after a test drive.
🔧 Mechanic's note — Ray Delgado
In my experience, the wrong coolant in the wrong car is a slow-motion disaster. If the color doesn't match what's already in there, flush it completely.
All Done!
Test your repair before closing everything up. If something doesn't work right, double-check your steps.
⚠️ Common Mistakes to Avoid
- • Not properly draining the coolant, leading to spills and environmental hazards
- • Forgetting to disconnect the battery before starting the repair, posing electrical risks
- • Over-tightening bolts, which can damage components or cause leaks
