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).