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knocking 350

  1. crazyforgms
    Hii there i have 98 k 1500 with 213.00 miles on it . when i start it it sounds like a duremax 6.6 after it wamers up you cant here it i used 10w40 oil & lucas oil treatment any tips how to stop it knocking with out rebuilding it ?

    thanks crazyforgms
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  2. 90fxstc
    I hope that you get some feedback here. I have the same knock and I hear that its common My truck has 180k and it runs just fine. However it knocks on the start up almost every time. I tried the Lucas oil additive too and it works a little. I guess I would like to know what is knocking exactly. How common is this?
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  3. Big_Mike
    Sorry to be the bringer of bad news, but if it's knocking, it's probably near the end of its life. I had the same problem. My engine would rattle badly on the bottom end upon initial start up and then after around thirty seconds to a minute, stop. I noticed when I was at a stop light the oil light would come on and my oil pressure gauge would drop dangerously low (meaning worn out bearings). I have a 93 Chevy 1500 with a 5.7. To be honest, that Lucas oil might work for a while, but essentially it's like putting a band aid on a gash. The best repair would be an engine overhaul or replacement, depending on what you would like to do. Good luck fellow members.
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