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03 lb7 no brakes

2K views 12 replies 8 participants last post by  TexasRedNeck 
#1 ·
I have a 03 lb7 4x4 and I just changed all the metal brake lines and now I can't get the brakes to bleed right. The pedal will get kind of hard when pumping but never get completely firm. It will only start getting hard if I don't fully release it when pumping. Any ideas? Thanks
 
#3 ·
spend the 40-60 on a brake pressure bleeder. It pressurizes the lines and all you do is open the bleeders to get rid of the air and old fluid.
 
#4 · (Edited)
Open the bleeders one at a time starting with the right rear then left rear, right front, left front and let gravity pull the fluid through, in other words let it drip on its own for a little while and see if it helps, can't hurt. Sometimes it works sometimes it don't. Then find a gravel road or somewhere that you can activate the ABS.
 
#5 ·
I just did the same job on my 03 lb7. Make sure you have no leaks and try bleeding with the truck running. I also took mine for a short drive and locked it up a few times to try to ******* bleed the and module. Worked for me!
 
#6 ·
Ok I tryed gravity bleed today didn't seem to help much. I can't find a leak anywhere on this thing. I've replaced the master cylinder with no change I bench bleed it too. I'm not getting any air at the bleeders so I'm going to try the gravel road method tomorrow and bleed with it running to. If that doesn't work I guess I'll get a pressure bleeder.
 
#9 ·
Have you slid a couple times yet?

Make sure you're topped of and find a dirt road to slide down and activate abs. It should cycle out any air.

Then you will need to bleed at the calipers again to release it
 
#11 ·
I have the Dorman stainless steel lines, the one from the ABS junction under the drivers side to the rear end split did not fit it was too long for my extended cab. I have bending and flaring tools and cut and shortened it to fit.
 
#12 ·
How about using a hand pressure bleeder to push fluid into the system from each bleeder screw?

Never needed to do it myself but have read good things.
 
#13 ·
I had issues bleeding mine after changing the flexible lines. Couldn't get my pressure bleeder to work and had to do it all by old fashioned pumping and holding the pedal. Even then I had to have a friend with a scan tool activate the ABS while pressure bleeding to get the air out of the module. You're going to have to activate the abs while bleeding
 
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