Overhaul Engine Internal Components

Safety Precautions: Ensure the vehicle is on a flat surface, the battery is disconnected, and the engine is completely cool before starting. Use appropriate jack stands if lifting the vehicle.

Required Tools: Engine hoist, torque wrench, socket set, plastigage, new rod bearings, new piston rings, and manufacturer-specified engine oil.

1. Remove the engine from the vehicle chassis using an engine hoist.
2. Disassemble the engine block to access the crankshaft and connecting rods.
3. Inspect the crankshaft journals for scoring or excessive wear; have the crank machined by a professional shop if necessary.
4. Replace the connecting rod bearings using plastigage to verify correct oil clearances as specified in the Toyota Hilux service manual.
5. Install new piston rings and reassemble the internal components, ensuring all fasteners are tightened to the precise factory torque specifications.
6. Refill with high-quality oil and perform a slow, controlled break-in cycle.

Verify the Fix: Start the engine and allow it to reach operating temperature. Monitor for the absence of deep knocking sounds across all RPM ranges and ensure oil pressure readings remain within the manufacturer's specified range.

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