GM 3800 V6 Torque Specifications by Engine Code

Note: The values below are approximate and intended as a general guide. Always verify the correct torque specs and procedures in the official GM Factory Service Manual or a trusted repair guide for your specific engine code and model year.

Series I Engines (e.g., LN2, LM7)

Component Fastener Torque Specification Notes
Cylinder Head Assembly Head Bolts/Studs 30–40 ft-lbs (Initial), 90–100 ft-lbs (Final) Follow specific tightening sequence for even clamping load.
Main Bearing Caps Cap Bolts 90–100 ft-lbs Tightening order is critical.
Connecting Rods Rod Bolts 18–20 ft-lbs Use a calibrated torque wrench; follow crisscross pattern.
Intake Manifold Manifold Bolts 18–20 ft-lbs Ensure even torque distribution.
Exhaust Manifold Manifold Bolts 18 ft-lbs Verify exact spec for your model.
Valve Covers Cover Bolts 7–9 ft-lbs Avoid over-tightening to prevent gasket damage.
Oil Pan Pan Bolts 8–10 ft-lbs Hand-tighten first, then torque to spec.
Timing Cover & Chain Tensioner Bolts 15–18 ft-lbs May require a two-step procedure.

Series II Engines (e.g., L32, L67, etc.)

Component Fastener Torque Specification Notes
Cylinder Head Assembly Head Bolts/Studs 30–40 ft-lbs (Initial), 90–100 ft-lbs (Final) Sequence may have slight procedural tweaks.
Main Bearing Caps Cap Bolts 90–100 ft-lbs Follow the recommended sequence exactly.
Connecting Rods Rod Bolts 18–20 ft-lbs Use a quality, calibrated torque wrench.
Intake Manifold Manifold Bolts 18–20 ft-lbs Ensure even clamping force.
Exhaust Manifold Manifold Bolts 18 ft-lbs Check for model-specific variations.
Valve Covers Cover Bolts 7–9 ft-lbs Use caution to prevent gasket crushing.
Oil Pan Pan Bolts 8–10 ft-lbs Verify torque after initial hand-tightening.
Timing Cover & Chain Tensioner Bolts 15–18 ft-lbs Specifications may differ slightly.

3800 V6 Series 2 & 3 Headbolts

New bolts on cylinder heads in sequence in picture 37 ft lbs then 120 degrees.

3800 Rocker Arms

11 ft lbs on rocker bolts with new bolts ( no exceptions).