1. Low Oil Pressure: If the engine oil level is low or the oil is old and degraded, it can lead to insufficient oil pressure. This can cause the engine components to knock as they lack proper lubrication.
2. Worn Engine Bearings: The bearings in the engine support the crankshaft and connecting rods. Over time, these bearings can wear out, causing a knocking sound.
3. Piston Slap: Piston slap occurs when the pistons inside the engine have become loose and slap against the cylinder walls. This is common in older engines with high mileage.
4. Lifter Tick: Lifters, also known as hydraulic valve lifters, control the opening and closing of valves in the engine. When they become worn or dirty, they can produce a knocking sound.
5. Spark Knock: This occurs when the air-fuel mixture in the combustion chamber detonates prematurely, resulting in a knocking noise. It can be caused by various factors such as low-quality fuel, incorrect spark timing, or carbon deposits in the engine.
6. Failed Rod Bearing: If a rod bearing fails, it can cause a loud knocking or tapping sound.
7. Failed Main Bearing: A failed main bearing can also cause a knocking noise, particularly when the engine is cold and the oil is thick.
If you hear a knocking noise in your Chevy Tahoe, it's important to address it promptly. Ignoring it can lead to severe engine damage. Have your vehicle inspected by a qualified mechanic to diagnose the exact cause of the issue and recommend the best course of action for repairs.
