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Vacuum Line

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by blank, Sep 6, 2005.

  1. blank

    blank Registered Member

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    Does the 700r4 tranny on the 83 blazer have the vacuum line on it like the t350 did? near the rear of the tranny. Mine is shifting weird holding in on shifting to second and then if feels like it slips a little and then goes straight tothird or OD.

    Any ideas?
     
  2. blank

    blank Registered Member

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    Is there anybody out there?
     
  3. 88sub4x4

    88sub4x4 1/2 ton status

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    I'm not sure of the earlier year 700's but the newer ones, 87+, were not vacuum modulated. Check the color of your fluid, if it's really brown/black and smells burnt you may need a rebuild. The 2nd gear shift solenoid is a common failure on high mileage units. The truck will hold first almost forever, then bang into 2nd, if it even does that. Although they recieve alot of bashing around here, the 700 is a good tranny. It doesn't hold up too well to heavy abuse, much like 10B axles, but when run properly with the proper cooling they will last just as long as the 3 speeds, and you save all that gas money with the overdrive on the highway, plus a lower first gear ratio then any of the three speeds.
     
  4. Desert Yeti

    Desert Yeti 1/2 ton status

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    I've never owned a 700, but I will submit that the symptoms you describe sound exactly like what a missing/leaking vacuum line does to a 3 speed... so good call if that's what it ends up being.
     
  5. dyeager535

    dyeager535 1 ton status Premium Member

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    No, there is no vacuum modulator on a 700R4. That's what the TV cable does.
     
  6. 87BrnRsd

    87BrnRsd 1/2 ton status

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    My 700r4 did the same thing. Check the shift modulator. Its on the drivers side bell housing of the transmission. There will be a round metal cap near the top....pry it loose with a screwdriver. Then pull out the metal piece inside. If the gear on the end is all stripped up, then you know that was the problem. Your getting scammed is it costs you more than $10 at a transmission shop for a new governor gear.
    -Harrison
     
  7. 88sub4x4

    88sub4x4 1/2 ton status

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    Ah, shift modulator, that's the word I couldn't remember and called a solenoid in my previous post. :bow:
     

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