3.6L Engine Complete Assembly for 2017-2025 Cadillac, Chevrolet, & GMC

A quick look at your own vehicle makes sure the right engine shows up:

• Check your VIN's 8th digit: Locate the 17-digit VIN on your driver's side dashboard or door jamb sticker. The 8th digit must be 'S'.
• Verify your RPO Codes (Cooling Option): Locate your vehicle's Service Parts Identification (SPID) label and look for the code V08. If you see V08, your vehicle has heavy-duty cooling, and this engine is not a direct match.
• Confirm your Drivetrain (FWD vs. AWD): Note whether your vehicle is Front-Wheel Drive or All-Wheel Drive to ensure correct oil pan and PTU mounting bracket transfer.

What the install really takes — plan and budget with confidence:

Special tools this job needs:

• Engine hoist with a heavy-duty load leveler
• Subframe/cradle support table or heavy-duty tall jack stands
• GM quick-disconnect fuel line tools
• High-end bi-directional scan tool
• Torque-to-yield (TTY) bolt replacement sockets/tools

Budget for these consumables at install:

• 5.7 to 6.0 quarts of Dexos1 Gen 2/3 approved 5W-30 synthetic engine oil
• New ACDelco PF63 oil filter
• 2 to 3 gallons of pre-mixed 50/50 GM-approved Dex-Cool coolant
• New intake manifold plenum gaskets and throttle body gasket
• 6 new OE-spec iridium spark plugs
• Brand-new OEM thermostat (GM PN 12678779) and housing seal
• Front and rear crankshaft seals
• New torque-to-yield (TTY) fasteners (subframe/cradle bolts, axle nuts, and flexplate-to-torque converter bolts)

What your vehicle’s computers will need after the swap:

What’s involved: Crankshaft Position (CKP) Variation Relearn (CASE learn)

While the engine will physically start and run without this procedure, the vehicle's computer will not recognize the micro-tolerances of the new engine's crankshaft reluctor wheel. This will trigger a flashing Check Engine Light, store trouble codes (such as P0300, P0315, or P1336), and disable misfire detection. If you reuse your vehicle's original Engine Control Module (ECM), security/immobilizer re-programming is not required.

Pro tips for a smooth first start-up — hand them to whoever does the install:

• FWD vs. AWD Oil Pan Swap: AWD models utilize a unique oil pan design to allow clearance for the Power Transfer Unit (PTU/transfer case). If the donor engine was pulled from a FWD vehicle, you must swap your original AWD oil pan and intermediate shaft brackets.
• Thermostat Location: The thermostat is located at the rear of the block, tucked beneath the intake manifold and fuel rails. It is exceptionally difficult to access once the engine is bolted into the vehicle. Replace it while the engine is on the stand.
• Aluminum Head Exhaust Studs: Because the exhaust manifolds are integrated directly into the aluminum cylinder heads, use extreme caution when unbolting and re-torquing these connections to avoid stripping the threads.
• Torque-to-Yield (TTY) Fasteners: Subframe/cradle bolts, axle nuts, and flexplate-to-torque converter bolts are one-time-use. You must replace them with new hardware.
• Fragile Plastic Components: Modern engines have numerous plastic cooling pipes, sensor connectors, and vacuum lines that become brittle with age and heat cycles.
• Grounding Connections: Ensure all critical ground straps between the engine, body, and transmission are clean, secure, and correctly reinstalled to prevent electrical issues.

Easy to get right once you know them:

• Ordering for a Traverse or Enclave: Assuming all GM 3.6L V6 engines from this era are identical. Traverse and Enclave use the LFY engine, which has entirely different mounting points, cylinder heads, and wiring harnesses.
• Ignoring the Heavy-Duty Cooling Option: This engine is designed for vehicles without heavy-duty cooling (RPO code w/o V08). If your vehicle has the V08 heavy-duty cooling package, this engine will not be a direct drop-in without swapping accessory brackets or oil filter adapters.
• Reusing the Thermostat: Skipping a new thermostat to save money often results in having to tear the intake manifold back off in a cramped engine bay just weeks after the swap.
• Assuming a 'Defective' Engine Due to Misfire Codes: Failing to perform the mandatory Crankshaft Position (CASE) Relearn procedure will cause a flashing Check Engine Light with P0300 misfire codes.
• Using Incorrect Oil: Not using the strict dexos1 Gen 2 specification oil can lead to premature timing chain wear.

Not issues with the units on this page — the manufacturer documented these for every engine of this family, wherever you buy one. Handy for your installer: