Crankshaft Main Bearing: Specifications

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 a bolt at a time in order to prevent the cap from being cocked.

Tighten the bolts to 70 N.m (52 lb ft) to fully seat the crankshaft main bearing caps. Loosen the bolts 360 degrees counterclockwise.

Tighten the bolts to 20 N.m (15 lb ft), then 40 N.m (30 lb ft).
Use J 45059 to tighten the bolts in steps: 35 degrees plus 35 degrees plus 40 degrees for a total of 110 degrees.

Install the side main bolts. Apply GM P/N 12345493 (Canadian P/N 10953488) or equivalent to the side main bolts.
Tighten the side crankshaft main bearing cap bolts to 15 N.m (11 lb ft). Use J 45059 to tighten the bolts an additional 45 degrees.

Crankshaft Main Bearing Cap Bolt
First Pass 40 N.m (30 lb ft)
Final Pass 110 degrees
Crankshaft Main Bearing Cap Bolt - Side
First Pass 15 N.m (11 lb ft)
Final Pass 45 degrees

Crankshaft Main Bearing Clearance - #1 0.0178-0.0406 mm (0.0007-0.0016 in)
Crankshaft Main Bearing Clearance - #2, 3 and 4 0.0229-0.0457 mm (0.0009-0.0018 in)