No 4 whel drive

Discussion in 'Shop Talk' started by Chas in Me, Dec 14, 2006.

  1. Chas in Me

    Chas in Me Well-Known Member

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    I recently took possession of an 1987 S-10 Blazer. It won't shift into 4 wheel drive. When I pulled the handle back to the neutral position, it madea grinding sound, but no 4 wheel. I'm not much of a mechanic, so what i want to know,is there a place I should look first to see if there is just something unhooked?
    Thanks for any info.
    Chas
     
  2. tiogacounty

    tiogacounty Well-Known Member

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    In sure others will provide more info. but I'll try. I had an s-10 pick-up of this vintage. As I recall the front axle actuator was a real piece of trash, engineering nightmare and it worked real poorly, then not at all. I don't recall how much the repair bill was, but the Chevy mechanic told me that it was a very common problem. Good luck.
     

  3. idahodave

    idahodave Well-Known Member

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    If your Blazer is like my '89 S10, all you need to do is pull the lever from 2HI back into 4HI. If you push the button on the top on the lever you can shift to neutral, then 4LO. Truck needs to stopped and in park to shift out of neutral without grinding. Sometimes I need to stop the motor in neutral to shift transfer case from low range thru neutral to high ranges. 2HI to 4HI is smooth....shoudn't need to hit neutral for 4wd.
     
  4. Chas in Me

    Chas in Me Well-Known Member

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    Thanks guys. I think there is a vacuum line unhooked. Will check it out tomorrow.
    I appreciate your answers.
    Chas
     
  5. Beeman

    Beeman Well-Known Member

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    pulling the lever shifts the transfer case into and out of 4wd. There is a vacum switch on the top of the transfer case. There should be a supply of vacum to one port of that switch at all times. when you engage the transfer case(move the lever) it activates the vacum switch to allow vacum to pass thru it and activate the vacum control that locks the frt. axle. the vacum control is either on the right fenderwell or on later years under the battery tray. Common problems are decayed vacum hoses, bad or plugged vacum switch on transfer case and possibly a bad actuator. If you can see the actuator you can physically watch it retract and pull the cable that engages the frt. axle.