Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2003 Chevrolet Express 1/2 Ton Van V6-4.3L VIN XFACTORY OEM SERVICE PROCEDURE
Fastener Tightening Specifications
Crankshaft Bearing Cap Bolt - Preferred Method
First Pass 20 Nm (115 ft. lbs.)
Final Pass 73 degrees
Crankshaft Bearing Cap Bolt - Optional Strategy 105 Nm (77 ft. lbs.)
Crankshaft Main Bearing Bore Out-of-Round 0.050 mm (0.002 inch)
Crankshaft Main Bearing Clearance #1 - Production 0.02-0.05 mm (0.0008-0.0020 inch)
Crankshaft Main Bearing Clearance #2, #3, and #4 - Production 0.028-0.058 mm (0.0011-0.0023 inch)
Crankshaft Main Bearing Clearance #1 - Service 0.0254-0.05 mm (0 0010-0 0020 inch)
Crankshaft Main Bearing Clearance #2, #3, and #4 - Service 0.025-0.063 mm (0.0010-0.0025 inch)
Crankshaft Main Bearing Bore Out-of-Round 0.050 mm (0.002 inch)
First Pass 20 Nm (115 ft. lbs.)
Final Pass 73 degrees
Crankshaft Bearing Cap Bolt - Optional Strategy 105 Nm (77 ft. lbs.)
Crankshaft Main Bearing Bore Out-of-Round 0.050 mm (0.002 inch)
Crankshaft Main Bearing Clearance #1 - Production 0.02-0.05 mm (0.0008-0.0020 inch)
Crankshaft Main Bearing Clearance #2, #3, and #4 - Production 0.028-0.058 mm (0.0011-0.0023 inch)
Crankshaft Main Bearing Clearance #1 - Service 0.0254-0.05 mm (0 0010-0 0020 inch)
Crankshaft Main Bearing Clearance #2, #3, and #4 - Service 0.025-0.063 mm (0.0010-0.0025 inch)
Crankshaft Main Bearing Bore Out-of-Round 0.050 mm (0.002 inch)
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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