Question about 1999 GMC Sierra

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99 GMC Sierra Fluid Leak Immediately after Getting Oil Change

My mechanic was busy and I needed an oil change. Went to a diff. Mech. As soon as I pulled away from the garage I noticed my brakes felt different. I had to press harder and it took longer to stop. After ten mins, my brake light came on. I checked Fluid, and it was low so I added some. I drove back to the mechanic's but it was closing time. We noticed the fluid leaking in the front of the truck, about a foot behind the bumper. He said it could be rusted lines and He will have to look at it tomorrow morning. Any suggestions or explanation on what could be wrong besides possible tampering????

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As an owner of three gmc sierras, i can attest that the brake lines that run along the frame rail under the master cylinder inherently rust away and break. I wouldnt neccesarily think it was tampered with. but do check the condition of all of the lines including the fuel lines for excessive rust.

Posted on Dec 11, 2008

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They are bad for that . there is a brake line that's runs from the drivers side under the radiator to the right front brake. had to change that one on mine a month ago... check the brake line under the drivers area inside the frame that's the other spot they rust out.... hope this helps....

Posted on Dec 11, 2008


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