Question about 1990 GMC Suburban

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1990 4x4 350 engine ,automatic trans. transmission just started to slip , doesn't want to shift out , some times it is like it isn't even in gear ..What is my first step to fixing the problem !!

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  • Mitchell Byrd Dec 28, 2010

    It just happened out of the blue , it was fine yesterday , but slips today .. The fluid is brown , the trans is only about 2 years old .. could it be a simple fix ???

  • Mitchell Byrd Dec 28, 2010

    My luck , Thanks for the imput !!!

  • Mitchell Byrd Dec 28, 2010

    Yes , the solution was helpful .. Not what I wanted to hear , but helpful !!!

  • Mitchell Byrd Dec 29, 2010

    I did pay for your advice and I thanked you , it said I was charged 10.00 for your answer , I don't know why you think I refused your advice , I accepted it ...



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Once the transmission starts to slip and you have verified the fluid level is ok that is it, the transmission must be removed and overhauled or a rebuilt not installed (I prefer this to doing an overhaul). This information is based on my 35 years as a Certified Master auto technician.

Posted on Dec 28, 2010

  • yadayada
    yadayada Dec 28, 2010

    The fact the transmission fluid id brown indicates sipping is taking place, it causes the fluid to overheat and burn very quickly, I am sorry but whom ever rebuilt the transmission did something wrong or used sub standard parts.

  • yadayada
    yadayada Dec 28, 2010

    As far as it worked fine yesterday, well i have lost count of how many times a customer has said that, with any thing mechanical there is a point where it works and then it doesn't, simple as that.


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This is a big job it is internal malfunctioning the transmission has to be removed and taken apart and assist.This is a serious repair and is a specialist repair.However your first step would be to perhaps take the truck in for further diagnostics and quote.I hope this advice will set you in the rite direction.

Posted on Dec 28, 2010

  • John Jon Dec 28, 2010

    Your trans mission has brown fluid not red clutch plates are burned up it is two years old as you say but you will rebuild or replace that transmission 25 years i have class A mechanical ability and hands experience i tried to be polite and very help full that's okay you will not have to pay for the advice you asked me for but you will pay $1500.00 or better for your transmission repair or replacement good luck to you.

  • John Jon Dec 28, 2010

    Correction you will have to pay for the premium on the advice you asked you reject my answer but looks as if though the premium is being applied to you so looks like your going to pay for the advice you requested and professionally removed.



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