Grand Cherokee 4WD V8-5.7L VIN 2 (2007)
Spark Plug: Service and Repair
Installation
INSTALLATION
NOTE: The 4.7L is equipped with copper core ground electrode spark plugs. They must be replaced with the same type/number spark plug as the
original. If another spark plug is substituted, pre-ignition will result.
Special care should be taken when installing spark plugs into the cylinder head spark plug wells. Be sure the plugs do not drop into the plug wells as
electrodes can be damaged.
Always tighten spark plugs to the specified torque. Over tightening can cause distortion resulting in a change in the spark plug gap or a cracked porcelain
insulator.
1. Start the spark plug into the cylinder head by hand to avoid cross threading.
2. Tighten spark plugs to 27 Nm (20 ft.lbs.). 3.7L & 4.7L.
3. The 5.7L is equipped with torque critical design spark plugs. Do not exceed 15 ft. lbs. torque. Tighten spark plugs to 18 Nm (13 ft.lbs).
NOTE: 5.7L does not use an O-ring
4. Before installing ignition coil(s), check condition of coil O-ring and replace as necessary. To aid in coil installation, apply silicone to coil O-ring.
5. Install ignition coil(s).
