What is the normal coolant temperature for a 5.7 Hemi Ram 1500?
On a typical 5.7L Hemi Ram 1500, the engine coolant temperature sits around 195–205°F (90–96°C) once the engine is fully warmed and operating normally. The thermostat commonly opens around 180°F (82°C), and the cooling system maintains that range through radiator heat exchange and cooling fans as needed.
Understanding the 5.7 Hemi cooling system
The 5.7 Hemi uses a traditional closed-loop cooling system with a primary thermostat, water pump, radiator, and cooling fans. When the engine is cold, the thermostat remains closed to help the engine reach operating temperature quickly; at about 180°F (82°C) it starts to open and gradually modulates to keep the coolant within the target operating window. The radiator, coolant flow, and electronically controlled fans work together to shed heat when needed. Dashboard gauges provide a best-guess reading, and actual temperature can vary slightly depending on sensor placement and driving conditions.
Normal temperature range to expect
Below are the typical temperature markers you’re likely to see under normal driving conditions.
- Normal operating coolant temperature: approximately 195–205°F (90–96°C) once fully warmed.
- Thermostat opening point: around 180°F (82°C).
- Cooling fan activation threshold: roughly 205–215°F (96–102°C).
- Under heavy load or towing, temperatures can briefly rise toward 210–230°F (99–110°C) if cooling is challenged.
In routine driving, the coolant temp should settle in the mid-190s to mid-200s Fahrenheit. If readings consistently sit outside this range, it can indicate a cooling-system issue that warrants inspection.
Gauge vs actual temperature
The dashboard gauge is an approximation. For precise readings, use an OBD-II scanner or a digital infrared thermometer to verify the coolant temperature reported by the sensor.
What to do if your temperature is out of range
If your readings fall outside the normal window for more than a short period, consider these checks and steps:
- Inspect coolant level when the engine is cool and top off if needed with the correct 50/50 mix.
- Check for leaks, damaged hoses, or a failed radiator cap.
- Test the thermostat operation and replace if it’s stuck open or closed.
- Verify radiator and condenser cleanliness; ensure airflow is unobstructed.
- Confirm cooling fans are functioning; check relays, fuses, and wiring.
Regular maintenance, including coolant replacement at the manufacturer’s intervals, helps maintain the proper temperature range and engine longevity.
Summary
The normal coolant temperature for a 5.7 Hemi Ram 1500 sits around 195–205°F (90–96°C) once the engine is fully warmed, with a thermostat that opens around 180°F (82°C) and cooling fans that engage to prevent overheating. If temperatures stay outside this band, investigate the cooling system parts and fluids to prevent heat-related engine damage.
