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Crankshaft Main Bearings

NOTE: Crankshafts are specially treated and can only be ground by the factory.
  1. Use Plastigage method to measure main bearing clearances. Standard crankshafts are marked with Red or Blue dots on side of counterweights. On 2.7L engine, crankshaft is cast with a "W" on center counterweight. The 3.2L engine has a code "K".
  2. Factory ground crankshafts are identified by paint stripes marked on 1st counterweight. This indicates either 1st, 2nd, or 3rd undersize. Two undersizes are available for the 2.7L engine and, 3 undersizes for the 3.2L engine.
  3. Factory ground crankshafts are supplied with bearings which are also color coded. If Red and Blue bearing shells are used in combination, ensure shells of same color are on same side of crankshaft. For example, all Red bearings in cylinder block and all Blue in main bearing caps.
  4. If 3 different color (Yellow, Green, and White) bearings are used, match bearing shells to color codes on bearing journals and crankcase. If crankcase mark is missing, install both shells according to crankshaft color code.
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