Dodge Ram Truck 1500-2500-3500. Manual — part 238

5.9L Diesel

The Engine Coolant Temperature (ECT) sensor on the
5.9L diesel engine is located near the thermostat
housing.

WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING. COOLING SYSTEM
MUST BE PARTIALLY DRAINED BEFORE REMOV-
ING THE COOLANT TEMPERATURE SENSOR.

1. Partially drain the cooling system (Refer to 7 -

COOLING - STANDARD PROCEDURE).

2. Disconnect the electrical connector (3) from the

sensor (3).

3. Remove the sensor from the cylinder head.

8.3L V-10

The Engine Coolant Temperature (ECT) sensor on the
8.0L V-10 engine is threaded into the thermostat hous-
ing.

WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING. COOLING SYSTEM
MUST BE PARTIALLY DRAINED BEFORE REMOV-
ING THE COOLANT TEMPERATURE SENSOR.

1. Partially drain the cooling system (Refer to 7 -

COOLING - STANDARD PROCEDURE).

2. Disconnect the electrical connector from the sen-

sor.

3. Remove the sensor from the cylinder head.

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ENGINE

DR/DH

INSTALLATION

3.7L V-6

1. Apply thread sealant to sensor threads.

2. Install sensor to engine.

3. Tighten sensor to 11 N·m (8 ft. lbs.) torque.

4. Connect electrical connector to sensor.

5. Replace any lost engine coolant. (Refer to 7 -

COOLING - STANDARD PROCEDURE).

4.7L V-8

1. Apply thread sealant to sensor threads.

2. Install sensor to engine.

3. Tighten sensor to 11 N·m (8 ft. lbs.) torque.

4. Connect electrical connector to sensor.

5. Replace any lost engine coolant. (Refer to 7 -

COOLING - STANDARD PROCEDURE).

DR/DH

ENGINE

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5.7L V-8

1. Apply thread sealant to sensor threads.

2. Install sensor into engine.

3. Tighten sensor to 11 N·m (8 ft. lbs.) torque.

4. Connect electrical connector to sensor.

5. Carefully bolt air conditioning compressoronto the

front of engine. Refer to Heating and Air Condition-
ing section for information.

6. Install accessory drive belt (Refer to 7 - COOLING/

ACCESSORY DRIVE/DRIVE BELTS - INSTALLA-
TION).

7. Replace any lost engine coolant. (Refer to 7 -

COOLING - STANDARD PROCEDURE).

5.9L Diesel

1. Install sensor (3) to engine.

2. Tighten sensor to 18 N·m (13 ft. lbs.) torque.

3. Connect electrical connector (2) to sensor (3).

4. Replace any lost engine coolant (Refer to 7 -

COOLING - STANDARD PROCEDURE).

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ENGINE

DR/DH

8.3L V-10

1. Apply thread sealant to sensor threads.

2. Install sensor to engine.

3. Tighten sensor to 11 N·m (8 ft. lbs.) torque.

4. Connect electrical connector to sensor.

5. Replace any lost engine coolant (Refer to 7 -

COOLING - STANDARD PROCEDURE).

THERMOSTAT-ENGINE COOLANT

DESCRIPTION

GAS ENGINE

CAUTION: Do not operate the engine without a
thermostat, except for servicing or testing.

The 3.7L/4.7L/5.7L engines use a pellet-type thermo-
stat that controls the operating temperature of the
engine by controlling the amount of coolant flow to the
radiator. The 8.3L engine uses a movable sleeve type
thermostat. On all engines the thermostat is closed
below 195°F (90°C). Above this temperature, coolant
is allowed to flow to the radiator. This provides quick
engine warm up and overall temperature control.

Coolant leakage into the pellet container will cause the
thermostat to fail in the open position. Thermostats
very rarely stick. Do not attempt to free a thermostat
with a prying device.

DR/DH

ENGINE

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