Crankshaft and Bearings Installation

WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Torque To Yield (TTY) bolts used on cylinder head and main bearing cap bolts may bend or break during removal. Interaction between TTY bolt and threads may cause bolt to bend or break during removal. To minimize this problem, prior to removing TTY bolts, perform the follwoing:

Using an appropriate size punch and hammer, rap head of each bolt. Vibration produced by this procedure will assist in a successful removal.
If a bolt breaks during disassembly, a broken bolt Extractor Kit (EN-47702) has been released to assist in removal of remaining bolt segment. Many times the remaining bolt fragment will back out easily with a pick tool or reverse twist drill bit. NEVER reuse TTY bolts. Always make sure block threaded holes are clean and DO NOT place oil or threadlock on NEW bolts. See GM TSB 05-06-01-026B ON TORQUE TO YIELD BOLT BREAKAGE .

Tools Required

J 36660-A Torque Angle Meter

Install the upper crankshaft main bearings into the block.

Fig 1: Installing Upper Crankshaft Main Bearings Into Block
Courtesy of GENERAL MOTORS CORP.
Lubricate the upper crankshaft main bearing surface with clean engine oil.
Install the crankshaft.

Fig 2: Installing Crankshaft
Courtesy of GENERAL MOTORS CORP.

IMPORTANT: Refer to the pin stamp on the crankshaft main bearing caps for sequence and direction of installation. The pin stamp arrow points to the front of the engine.
Install the lower crankshaft main bearings into the main bearing caps.
Lubricate the lower crankshaft main bearing surface with clean engine oil.
Install the crankshaft main bearing caps.

Fig 3: Installing Crankshaft Main Bearing Caps
Courtesy of GENERAL MOTORS CORP.

IMPORTANT: The crankshaft main bearing cap stiffener is directional. The end marked front goes to the front.
Install the crankshaft main bearing cap stiffener.

Fig 4: Installing Crankshaft Main Bearing Cap Stiffener
Courtesy of GENERAL MOTORS CORP.
Install new crankshaft main bearing bolts. Start the crankshaft main bearing cap bolts by hand. Ensure the bottom of the crankshaft main bearing cap is parallel to the block surface.

Fig 5: Installing Crankshaft Main Bearing Bolts
Courtesy of GENERAL MOTORS CORP.

NOTE: Refer to FASTENER NOTICE in Cautions and Notices.
Tighten the crankshaft main bearing cap bolts in equal increments.
Tighten
1. 9.1. Tighten the crankshaft main bearing cap bolts to 25 N.m (18 lb ft) in sequence.
2. 9.2. Use J 36660-A to tighten the crankshaft main bearing cap bolts an additional 180 degrees.
  
  Fig 6: Tightening Sequence Of Crankshaft Main Bearing Cap Bolts
  Courtesy of GENERAL MOTORS CORP.