Engine - Revised Crankshaft and Bearings Installation: Overview
File In Section: 6 - EngineBulletin No.: 77-61-15
Date: October, 1997
SERVICE MANUAL UPDATE
Subject:
Section 6 - Engine Mechanical - Crankshaft and Bearings Installation
Models:
1997 Chevrolet and GMC C, K, G, and P Models
with 6.5L Diesel Engines (VINs S, Y, F - RPOs L56, L57, L65, L65-CMT)
The engine block for both production and for GMSPO (target engines) engine assemblies has been modified. The crankshaft bearing cap retaining bolt diameter at positions 2, 3, and 4 (outer bolts only) have been changed from 12 mm to 10 mm. This requires the use of a revised torquing sequence. Prior to installing the crankshaft in any 6.5L engine, verify the type of bolts used for the crankshaft bearing caps. For engines built prior to March 13, 1997 (all bolts are 12 mm), use the vehicle model year Service Manual's existing procedure. For engines built after March 13, 1997 (all inner bolts are 12 mm, outer bolts at positions 1 and 5 are 12 mm, and outer bolts at positions 2, 3, and 4 are 10 mm), use the information provided in this bulletin. This information is also available in the 1998 Service Manual.