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Discussion Starter #1
Just changed the steel brake line on my 99 Silverado that runs from the ABS box under the frame to the port on the master cylinder closest to the back of the truck. My questions is...where do I bleed the system? Do I need to bleed at all four corners, or at the master cylinder, or somewhere else? Anyone who has any experience doing this can you guide me through the process, Ive never dealt with ABS brakes and bleeding them. It would be easy if I replace a line that went from the master cylinder to the front wheels...id bleed both fronts. But this line runs from the master cylinder to the ABS unit so Im clueless. Any help?
 

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Discussion Starter #2
Well i started to bleed the drivers side front with my vacuum bleeder. Got in the truck to test the brakes...turned it on...pumped brakes...they started to feel firmer until ANOTHER line broke. At this point I am replacing all four lines that run back to the abs unit becasue they all have bad surface rust and I dont know hwen another will go out on me...this sucks!!
 

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I'm on a mission
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once you replace all the lines i believe it's l.r., r.r., r.f., l.f, double check that but i did brake lines on a 2001 about a year ago and the service manual give a specific bleeding order
 

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Discussion Starter #5
Thanks. Also has anyone replace their hard lines on 99-02 1/2 ton 4x4. Im looking to get pre bent stainless lines but Im having a hard time finding them Found a set for 3/4 ton but would think they are different. I may just have to bend my own.
 

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IIRC, the ABS valves need to forced open with a TECH II while bleeding. This allows air at the actuator and dump valves to travel to the bleeders. It's basically a four corner bleed with the computer attached.

AFTER DOING A DRIVEWAY BLEED WITHOUT THE COMPUTER, ACTIVATE THE ABS ON AN ABANDONED ROAD AT 8MPH. IF THE PEDAL DROPS, IT'S NEEDS THE ABS BLED CORRECTLY. IF IT DOESN'T DROP BUT SIMPLY SHUDDERS, YOUR DONE.

My dealer charges $65 to do it right.
 

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HOT AIR BALLOON OWNER
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You start at the right rear...
 
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