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AFM Lifter collapse

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    • #643269
      Ineed2xlr8
      Participant

      My 2015 Silverado lost compression in the number 4 cylinder. After doing some research, it appears to me that the AFM lifter has collapsed. It still doesn’t make any sense that the cylinder would lose compression. It doesn’t hold the valve open. Can anyone explain to me why this happens? Thanks, Scott

    • #643584
      Ineed2xlr8
      Participant

      After pulling the valve cover, we noticed a bent push rod. We replaced it and still no compression and no rocker arm movement. I guess the next step is to pull the head.

    • #646036
      Ineed2xlr8
      Participant

      We discovered that number 4 lifter on the AFM has collapsed. I have had the heads cleaned resurfaced and tested. No problems. I have ordered a AFM delete cam kit and a programmer. AFM is going away…

    • #684575
      leew222
      Participant

      This is a common problem that GM should Recall along with the transmissions.

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