Fastener Tightening Specifications - Main Bearing
Adjust the crankshaft bearing bridge adjusting sleeves until the bushings do not contact the engine block when the bridge is fully seated.
Tighten the main bearing cap bolts in three passes to 50 Nm (37 ft. lbs.) + 60° + 15°.
Apply thread locking compound Loctite 272, GM P/N 12345493 or equivalent, to the crankshaft bearing bridge adjusting sleeves.
Adjust the crankshaft bearing bridge adjusting sleeves until the bushings firmly contact the engine block.
Install the crankshaft bearing bridge bolts (2).
Tighten the crankshaft bearing bridge bolts to 20 Nm (15 ft. lbs.).