The Doge Ram 1500 is available with the following engines: 3.7 L, 3.9 L, 5.2 L, 5.9 L, 8.0 L, 4.7 L and 5.7 L. The spark plugs in all of these Ram engines need to be replaced every 30,000 to 60,000 miles. Though Dodge Ram engines vary in size, the basic process of replacing the spark plug is the same. The difference is the location and access to the spark plugs.
Disconnect the Dodge Ram model's negative battery cable and allow the engine to cool. For 3.7, 4.7 and 5.7 L engines, remove necessary air filter tubing at the throttle body to gain access to the spark plugs.
Locate the spark plug wires and gain access to the wire boots. On the 3.9, 5.2, 5.9 and 8.0 L engines, the spark plug wires are located across the sides of the engine with heat shields around the boots of the wires. On the Ram 5.7 L engine, eight of the 16 spark plugs are under the ignition coil. Remove the coil to access the spark plugs. The other eight spark plugs are located along the sides of the engine. The 3.7 and 4.7 L Ram engines have their spark plugs under each ignition coil.
Turn one spark plug wire by the boot one-half turn to the right and one-half turn to the left to loosen the wire. Pull back on the wire boot and remove it from the spark plug.
Cover the end of the spark plug with the socket and turn it counter-clockwise to unscrew and then remove the spark plug.
Apply anti-seize compound to the threads of the new spark plug and inside the wire boot.
Insert the new spark plug into the cylinder well and tighten it manually. Test the tension with a tension tester tool. A 5.7 L engine requires a tension of 11 to 15 ft-lbs. The 3.7 and 4.7 L engine's spark plug tension needs to be set between 15 to 20 ft-lbs. The 3.9, 5.2, 5.9 and 8.0 L engines require a tension between 26 and 30 ft-lbs.
Reconnect the spark plug wire and move on to the next plug. Continue the process until all of the spark plugs are replaced.
Replace all of the items that were removed in Steps 1 and 2.
