BRAKE line replacement

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Welderman85

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I just picked up an 03 that needs brake lines there not real bad just bad by the abs module. What the best way ? The doorman line kit or just replace what's real bad? Also do I need to worry about the fluid leaking out from the master cylinder and it going dry while I replace the lines and the same question for the abs box. Thank you
 

Scottydoggs

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you really dont want the abs module to go dry, if it does you'll need a tech 2 scanner or the likes to bleed it out. so find a way to plug the hole once you pull a line from it.
 

nonickatall

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you really dont want the abs module to go dry, if it does you'll need a tech 2 scanner or the likes to bleed it out. so find a way to plug the hole once you pull a line from it.
That is not true. If the ABS is empty I takes a little longer to bleed the system, but it works without scanner. With scanner it's faster.
To bleed you need some device like a pressure bleeder.
 

nonickatall

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I just picked up an 03 that needs brake lines there not real bad just bad by the abs module. What the best way ? The doorman line kit or just replace what's real bad? Also do I need to worry about the fluid leaking out from the master cylinder and it going dry while I replace the lines and the same question for the abs box. Thank you
It's quite a lot of work but I would replace the whole line, it is likely corroded thin near the abs and near the rear axlemmm
 

strutaeng

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Top off the fluid level on the reservoir and don't let run dry, otherwise you have to start all over again.

I would pull out all the old fluid with a turkey baster, pour new fresh fluid, then flush each wheel until fresh fluid runs clear, then bleed normally.
 

Scottydoggs

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What about letting the master cylinder run dry
if you can swap the line real fast while making sure the master never goes dry you'll have no air introduced into the system, other then the new line of course.

a piece of vac line and a small bolt can seal off the end of then new line so its not leaking all over the place as your getting it mounted up. or vac line caps will work if you have any handy.
 

Scottydoggs

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How long should this project take. As a guess
if you've used a flair tool before id say a hr or less. you can also go the frowned upon way.....aka compression fitting, (ive used em in the past and had no issues at all, also found them on both of my front brake lines on my tahoe when i got it. they are still there and working) cut the break area out with a small pipe cutter on both sides and install the compression fitting. way less than a hr for that way.

either way it would be best to remove the line from the union at the soft line, just so you have a easier go at the repair work on that side of the line. cutting and flaring it.
 

tom3

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If you will be flaring any lines the new Nicop lines work really well. Doing factory routing of brake/fuel lines is a real pain in the ...... I usually don't try it, just do it as I can without any high spots that trap air.
 

brasil

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replaced all of the brake lines last week ( 03 Tahoe from a good friend of mine ) 20 hours. all together. But I had to fight with the Nicop lines, because some of them i.e the one that goes from the ABS Block to the right front wheel was WAY to long. So I had to recurve the line over and over again ..until it looked like the factory routing. Biggest pain was the rear one that runs besides the fuel tank.

But after all was set and done...we were very happy about the result ! And of course... happy to be able to stop the Tahoe - while pushing the brake pedal.

... and yeh, we used a AUTEL Maxpro to bleed the ABS block ...within 1-2 minutes you are done. Great tool !
 
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OBSandaNNBS

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I just picked up an 03 that needs brake lines there not real bad just bad by the abs module. What the best way ? The doorman line kit or just replace what's real bad? Also do I need to worry about the fluid leaking out from the master cylinder and it going dry while I replace the lines and the same question for the abs box. Thank you
If you haven't bent and flared lines before...get the kit.
I've never flared a line but I've done a whole truck.
I used the stainless dorman line kit for my 97...not the same truck I know but the kit saved me hours and more importantly, frustration. Totally worth the money, I won't use anything else.
I did have to fight with one but it's been rocking for 4 years
 

blondie70

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To stop the master cyl from running dry when you open the system....figure out a way to hold the brake pedal down about half way or even all the way down. This shuts off the refill ports for the master cyl. I use a piece of 2 x 4....but secure it becuz once you open the system it may want to fall as no resistance is on the pedal. Good Luck
 

Eric Thomas

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It's quite a lot of work but I would replace the whole line, it is likely corroded thin near the abs and near the rear axlemmm
I pulled the ABS unit after disconnecting all lines, used a dental pick to clean the threads. Replaced all brake line with the GM coated lines, there were a few that I wasn't able to get in in that instance I used nickel/copper lines. It took me a few days because I was unable to separate the body from the frame. Flared all the lines myself but first I bought some practice lines just about 6 ft two or three of them and then proceeded to spend about an hour doing it to make sure that I got it right before I did it on the line
Then I used one of those pumps that holds about three and a half liters of brake fluid hooked it up to the master cylinder after I felt it and pumped it up through about 16 PSI and went around and got bled every wheel starting at the furthest from the ABS unit. It was worth the $125 or$140 I paid. Worked out great no problems and no scanner.
 

Potatonemo

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Made a thread on this but wanted to ask ya’ll. Got the all of the brake lines replaced with Dorman ones. One of the brake lines to the Module has a minor leak. Loosened it up, tightened it multiple times but it still keeps leaking. Anyone have this issue?
 

6speedblazer

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the dorman SS lines need to be TIGHT to not leak. I had to really wrench on all mine to get them to seal up.
 

Potatonemo

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the dorman SS lines need to be TIGHT to not leak. I had to really wrench on all mine to get them.
Only thing I was worried about was over tightening them to the point it may break.
I’m guessing you tightened them has hard as you could?
Thanks for the reply!
 

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