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Transfer case noise

Discussion in 'GM Powertrain' started by guzjimmy, Nov 17, 2012.

  1. guzjimmy

    guzjimmy New Member

    Hello all, new to this forum but not new to working on vehicles of all sorts.
    Current fleet includes 2007 HHR, 2002 Malibu, 1966 Chevelle SS, 1984 Chev 3/4 4x4, 1995 Pontiac Transport, 1968 Ford Bronco and the curent problem child a 2002 GMC Jimmy.
    The Jimmy just had the motor replaced (I bought it with the motor failing) and during the swap I visibly damaged the front diff actuator cable. After the motor was running I tried the 4x4 (4 button electronic NP8 option) and everthing worked. Didn't like the look of the kinked cable so I replaced it.
    At first startup the service 4x4 light went on and hasn't been off since and the transfer case is locked in 4x4. During the actuator cable swap I dissconnected the cable sensor and re-attached without incident.
    Now when the 2HI position is requested I can hear the transfer case motor running and I get some clunking on the RH kickpad but the 4x4 light flashs back on and the front driveshaft is engaged but the front actuator has pulled the RH front wheel out and it is dissengaged.
    Tried removing the battery for a day (in the hope of clearing the transmission codes if any) then re-attaching and still get the same condition. Have an OBD11 reader and cleared one misfire code (old spark wires = replaced) but no other codes showing via reader.

    HELP!
    Last edited: Nov 18, 2012
  2. SurrealOne

    SurrealOne Former Member ROTM Winner 1000 Posts

    Welcome! :great:
  3. retired2001

    retired2001 Epic Member 5+ Years 5000 Posts

    Welcome to the G M T C ! I think you might get more responses if you would post your problem in one of the "Tech." forums. Good luck!
  4. donyms

    donyms Rockstar 4 Years ROTM Winner 1000 Posts

    Welcome to the club Jimmy, it's good to have you aboard......... :glasses:
  5. Conlan Rose

    Conlan Rose Active Member 2 Years 1000 Posts

    :sign0016: I hope that you find the Info you need.
  6. 1953bowtieguy

    1953bowtieguy Member 2 Years 500 Posts

    Welcome to the club buddy.
  7. mfleetwood

    mfleetwood Rockstar 4 Years ROTM Winner 5000 Posts

    Welcome to the Club!!!

    I moved your thread to the correct section. Sorry, I cannot help you with your problem but someone should be along soon who can.
  8. RayVoy

    RayVoy Well-Known Member 2 Years 1000 Posts

    That front actuator cable is operated by a vacuum motor, the cable moves a disconnect actuator to tie the inner and outer passenger side drive axles together when in 4x4. I haven't looked at the vacuum setup for a few years, so, let me walk you through the electric setup it is probably the same, but it may only be a guide for you.

    When one of the 4x4 positions is requested by the driver, the t-case en-coder motor move to the 4x4 position to operate the forward clutch. A command is sent to the disconnect actuator to connect the axle halves. In the electric version, the complete operation of the disconnect actuator into the connect position closes a signal contact that sends a ready signal to the t-case control module which completes the encoder motor/clutch operation. In other words, power is not sent to the front wheels until the two axle halves are coupled.

    Could you have damaged the switch, or wiring?

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