Grand Cherokee 2WD V8-4.7L VIN J (2004)
Crankshaft Main Bearing: Service and Repair
STANDARD PROCEDURE-CRANKSHAFT MAIN BEARING- FITTING
MAIN BEARING JOURNAL DIAMETER (CRANKSHAFT REMOVED)
Crankshaft removed from the cylinder block.
Clean the oil off the main bearing journal.
Determine the maximum diameter of the journal with a micrometer. Measure at two locations 90° apart at each end of the journal. The maximum
allowable taper is 0.008 mm (0.0004 inch.) and maximum out of round is 0.005 mm (0.002 in.). Compare the measured diameter with the journal
diameter specification (Main Bearing Fitting Chart). Select inserts required to obtain the specified bearing-to-journal clearance.
CRANKSHAFT MAIN BEARING SELECTION
The main bearings are "select fit" to achieve proper oil clearances. For main bearing selection, the crankshaft position sensor target wheel has grade
identification marks stamped into it (Fig. 60). These marks are read from left to right, corresponding with journal number 1, 2, 3, 4 and 5. The
crankshaft position sensor target wheel is mounted to the number 8 counter weight on the crankshaft.
NOTE: Service main bearings are coded. These codes identify what size (grade) the bearing is.
MAIN BEARING SELECTION CHART-4.7L
INSPECTION
