Engine noise/knock
#1
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for the last couple weeks ive been noticeing a faint noise. it almost sounds like a bearing but my exhaust is so loud its hard to tell. the noise is louder when the car is colder and seems to quite up a good amount once it is warm. but even when the car is warm i can still faintly hear it. the car only has 47k so i was wondering if any one has come across bearings going this early or if anyone has any other ideas on what this coud be thanks
#3
Staging Lane
iTrader: (4)
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My opinion would be that the noise is from "piston slap". I believe that if a rod bearing is going, it would get louder as it warms up when oil is thinner, and with a few hundred more miles, it would get really loud.
My '00 5.3 makes a knocking noise on start-up for a minute or 2, then goes away. My mechanic buddy said piston slap is more common because the piston skirt diameter is slightly smaller than the piston head, and when the engine is cold and cylinders dry, the skirts "slap" the cylinder walls.
My '00 5.3 makes a knocking noise on start-up for a minute or 2, then goes away. My mechanic buddy said piston slap is more common because the piston skirt diameter is slightly smaller than the piston head, and when the engine is cold and cylinders dry, the skirts "slap" the cylinder walls.