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4wd Hi not engaging

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by tdjaster, Nov 20, 2011.

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  1. tdjaster

    tdjaster New Member

    (first time poster)

    2004 Silverado 1500 Z-71
    5.3 engine, automatic. 2wd/4wd selector is on the floor (not push button)

    My truck is not engaging when I select 4-HI. 2wd, Neutral, and 4-LO work correctly. Any thoughts?

    Thanks for your input.
    Last edited: Nov 20, 2011
  2. GMCErica

    GMCErica New Member Platinum Contributor 1000 Posts 100 Posts

    Hey, my thoughts: could be possibly corroded wires or in the connection to the 4x4 module
    -when you turn on your 4X4-if engage the 4x4, if you a sound like a CLICK-CLICK" noise that is your problem
    -It could also be the actuator; if there is no noise, it could be that.

    that's all i could think of.. good luck
  3. Megasaurus

    Megasaurus Member 100 Posts

  4. silveradotrailblazer

    silveradotrailblazer New Member 1000 Posts 100 Posts

    Welcome to the club. Also check the bushings on the shift linkage, when they get worn they won't shift correctly.
  5. tdjaster

    tdjaster New Member

    Thanks for the help. Can you be a little more specific? I'm a tinkerer/explorer when it comes to working on my truck. I'm certainly not at the mechanic level.

  6. GMCErica

    GMCErica New Member Platinum Contributor 1000 Posts 100 Posts

    If you go and search 4x4 issues in the forums, there are tons of people that post instructions, advice etc... that is just an idea too..
  7. RedneckRucker16

    RedneckRucker16 New Member

    Check the wiring at the actuator on ur front diff
  8. tdjaster

    tdjaster New Member

    SOLVED!!

    It was not the actuator (because that would have knocked out all 4wd, not just the 4HI). I was told by Advance Auto Parts that it would most certainly be a wiring issue. So I followed the wiring from the shift selector in the truck down to where it enters the transfer case. The plug that connects the wiring harness to the case is what was faulty (I'm blanking on what the name of the part is called).

    I got a new one from the Chevy dealership (because it is a part only available at dealerships) for about $50. It took me a while to work the old one out but was only a matter of minutes to put the new one back in.
  9. GMCErica

    GMCErica New Member Platinum Contributor 1000 Posts 100 Posts

    Hey! Glad that things worked out for you... :)

    ---------- Post added at 08:47 PM ---------- Previous post was at 08:45 PM ----------

    I predicted wires!! YEA! I am glad that it wasn't the actuator... Now you can drive without worrying about it :)

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