Fitting Bearings

Figure 16-Cylinder Block Main Bore Grade Marking Location:

The main bearings are "select fit" to achieve proper oil clearances. For main bearing selection, the block and crankshaft have grade identification marks.
The grade marks for the cylinder block main bearing bore grade is located on the pan rail just below the left side engine mount bracket. These marks are read left to right, corresponding to main bore 1, 2, 37 4.

Figure 15-Crankshaft Main Journal Grade Marking Location:

The grade marks for the crankshaft are located on the rear most crankshaft counter weight as shown in. The crankshaft journal grade marks are read left to right, corresponding with journal number 1,2,3,4.

Main Bearing Selection Chart-2.7L:

Use the Main Bearing Selection Chart to properly select the main bearings. For an example, if the main bore grade is 3 and the journal grade is 2, the proper select fit bearing would be (2) +0.003 mm (+0.0002 inch).

Figure 17 Main Bearing Grade Marks:

NOTE: Service main bearings have a number from 1 - 5 marked in ink on the bearing surface. For verification, use the Main Bearing Selection Chart for number to size identification.

The upper main bearing has a oil feed hole and a center groove to allow lubrication of the main journal and must be properly positioned in the block.