Engine knocking refers to the metallic sound an engine can produce when pressure is applied to the gas pedal. The noise may be a hollow knocking sound or it can be more of a rattling-type sound-in either case, it's not a sound you want to hear.
When an engine knocks, it releases pollution into the environment in the form of nitrogen oxide (NOx) and raw, unburned hydrocarbons (HCs). These two chemicals are poisonous gases that show up as yellowish-brownish in a polluted sky. They can also cause respiratory problems like Asthma and emphysema-a knocking engine is never a good thing.
There are some common causes for an engine to make these sounds.
Incorrect Combustion Process
An engine can knock because the combustion process is incorrect in some way. A "spark knock" is the result of combustion occurring too early. In a properly-firing cylinder, the flame front starts on one side of the piston and burns across the top to the other side, which creates a rapid and evenly-expanding gas that pushes down on the top of the piston. When the combustion process occurs too early, there is a random explosion in multiple locations on top of the piston; when this occurs, the flame front inside the cylinder collides with itself and does not burn evenly. An ignition timing that is too far advanced from the proper specification will create a spark knock because the combustion is initiated too early.
An engine can knock because it is too hot; this is another uneven combustion scenario that is caused by the air-to-fuel mixture "lighting off" by itself. If the cooling system does not keep the engine's combustion chamber temperature in check, the air-to-fuel mixture will begin to spontaneously explode. This is called "pre-ignition" or "pinging."
In addition to cooling system problems, pinging can be caused by improper gasoline octane, an overly lean air-to-fuel mixture, or a lack of proper exhaust gas recirculation. The exhaust gas recirculation system (EGR) was created to neutralize engine knocking by adding a small amount of exhaust gas to the air-to-fuel mixture going in to the combustion process, which limits the peak combustion chamber temperature.
Internal Mechanical Problems
Internal mechanical problems can also cause engine knocking. One such problem stems from excessive clearance inside the bearings in the connecting rods that transfer the downward movement of the pistons to crankshaft rotation. Each time the piston changes direction, there is a knock from the metal hitting metal. This is often referred to as a "rod knock." It is usually very rhythmic; it increases with engine speed and intensifies with engine load.
Other mechanical problems that lead to engine knocking are:
Be sure to properly inspect and verify the root cause of the knocking sound, as it can be tricky to pinpoint. You don't want to replace the entire engine only to find out that the knocking was coming from a cracked hub on the transmission flywheel or flex-plate. Ouch!
You should change engine oil in car or truck every 5,000 miles.
You should change your oil in your new truck every three thousand miles at least. You should check your oil once in a while. If its a new truck check oil every month.
Change it at the interval recommended by the manufacture.
Drop the oil pan
just drop the oil pan and dump the oil out..
Not enough oil was replaced. If this is not the case then oil pressure may be low.
how to change oil pump in a 2000 Chevy silverado 4.3 2 wheel drive truck
8000 gallons
Maybe one of these videos can help you: http://www.sutree.com/Learn.aspx?q=change+oil+in+chevrolet
the oil pressure in the engine rises when the truck is warming up causing the light to show, if continues after the truck has been running, change oil and oil pump.
To change the oil in a car or truck you first drain the old or used oil. Then run a flush and add the new oil. The biggest part of doing an oil change at home is proper disposal of the oil.
With a grease gun, every oil change.