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Crankshaft Main Bearing





Install the crankshaft main bearing cap bolts. Start the crankshaft main bearing cap bolts by hand. Ensure the bottom of the crankshaft main bearing cap is parallel to the bottom of the channel.
Tighten the crankshaft main bearing cap bolts in equal increments. Do not completely tighten one bolt at a time to prevent the cap from being cocked.
Tighten the bolts to 70 Nm (52 ft. lbs.) to fully seat the crankshaft main bearing caps. Loosen the bolts 360 degrees counterclockwise.
Tighten the bolts to 20 Nm (15 ft. lbs.) then 40 Nm (30 ft. lbs.)
Use J 36660-A to tighten the bolts in steps 35 degrees + 35 degrees + 40 degrees for a total of 110 degrees.
Install the side main bolts. Apply GM P/N United States 12345493, GM P/N Canada 10953488 or the equivalent to the side main bolts.
Tighten the side crankshaft main bearing cap bolts to 15 Nm (11 ft. lbs.). Use J 36660-A to tighten the bolts an additional 45 degrees

Crankshaft Balancer Bolt
First Pass 150 Nm (111 ft. lbs.)
Final Pass 76 degrees
Crankshaft Main Bearing Cap Bolt
First Pass 40 Nm (30 ft. lbs.)
Final Pass 110 degrees
Crankshaft Main Bearing Cap Bolt - Side
First Pass 15 Nm (11 ft. lbs.)
Final Pass 45 degrees
Crankshaft Main Bearing Bore Diameter 68.249 - 68.270 mm (2.6870 - 2.6878 inch)
Crankshaft Main Bearing Clearance-#1 0.0178 - 0.0406 mm (0.0007 - 0.0016 inch)
Crankshaft Main Bearing Clearance-#2, 3 and 4 0.0229 - 0.0457 mm (0.0009 - 0.0018 inch)