CYLINDER BLOCK/BEARING BOLT PRODUCTION CHANGES

A NEW 1/4" LONGER BEARING CAP BOLT P/N 22511818, IS REPLACING P/N 392190, FOR BOTH GAS AND DIESEL CYLINDER BLOCKS. ALL (10) HOLES IN THE DIESEL BLOCK HAVE A 1/4" DEEPER TAP AND A 1/4" LONGER COUNTER BORE. THE GAS BLOCK HAS THE DEEPER TAP AND COUNTER BORE AT NO. 5 BEARING CAP LOCATION ONLY. THE CHANGES BEGAN WITH THE 1981 START OF PRODUCTION SUBJECT: CYLINDER BLOCK AND BEARING BOLT CHANGES MODELS: 1981 C15 WITH 5.7 LITER DIESEL ENGINE A NEW 1/4" LONGER BEARING CAP BOLT, P/N 22511818, IS REPLACING P/N 392190, FOR DIESEL CYLINDER BLOCKS. ALL (10) HOLES IN THE BLOCK HAVE A 1/4" DEEPER TAP AND 1/4" LONGER COUNTER BORE. THE CHANGES BEGAN WITH THE 1981 START OF PRODUCTION.

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