Particles in the brake fluid

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df2x4

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I also plan on swapping the Master Cylinder from a 2004 Chevrolet Tahoe that I pulled from the junkyard last year.

I would do some serious research first and make sure you really want to do that. There has been quite a bit of discussion on the NBS master cylinder "upgrade" here, and the general consensus seems to be that while it will improve pedal feel/travel, you could actually be reducing stopping power in a panic stop situation. I would stick to the factory sized MC personally.

If pedal feel is an issue, bleed the ABS module with a Tech 2 or comparable bi-directional scan tool. This combined with braided lines and good pads/shoes has given me excellent results in both of my '97s (Both in pedal feel and stopping power, JB5 and JB6 brake systems respectively).
 

Boots97

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I just edited my original post to include some part numbers. Either one of those kits should work fine for your application. The Classic Tube kit has some hard metal sections for extra support where as the Russell kit is all flexible. I used a similar Russell kit on my red truck a few years back and everything is holding up great.
Thank You! I really appreciate that!
 

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You're welcome! Hopefully that gets rid of the gunk in your fluid.
 

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I would do some serious research first and make sure you really want to do that. There has been quite a bit of discussion on the NBS master cylinder "upgrade" here, and the general consensus seems to be that while it will improve pedal feel/travel, you could actually be reducing stopping power in a panic stop situation. I would stick to the factory sized MC personally.

If pedal feel is an issue, bleed the ABS module with a Tech 2 or comparable bi-directional scan tool. This combined with braided lines and good pads/shoes has given me excellent results in both of my '97s (Both in pedal feel and stopping power, JB5 and JB6 brake systems respectively).
I'm surprised to hear that. I've looked around and all I could find was one negative review on this forum regarding the NBS MC swap. I haven't had good luck with my current MC right now and even panic stops aren't great. I'm a pretty cautious driver and it ****** a lot of people off so I've rarely needed to panic stop and I've mostly done it when testing my brakes after bleeding the fluid.

I know there are scan tools out there that bleed this module. Does manually bleeding work too. I've seen a YouTube video on bleeding the ABS via a valve on the side.

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df2x4

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I'm surprised to hear that. I've looked around and all I could find was one negative review on this forum regarding the NBS MC swap. I haven't had good luck with my current MC right now and even panic stops aren't great. I'm a pretty cautious driver and it ****** a lot of people off so I've rarely needed to panic stop and I've mostly done it when testing my brakes after bleeding the fluid.

Do a search for "NBS master Cylinder quick take up calipers." Schurkey and I believe L31MaxExpress have both offered some insight on the subject. There are many threads on the subject but here's one, relevant discussion starts near the bottom of page two.

https://www.gmt400.com/threads/nbs-master-cylinder-swap.51713/page-2

Also kind of off topic, but sometimes the search function on this site leaves a little to be desired. If you go to the Google home page and type (without the quotes) "site:gmt400.com NBS Master Cylinder" for example, you'll get all the results for those words from gmt400.com only. This can be a handy trick for finding info when you don't remember a thread title or location.
 

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I know there are scan tools out there that bleed this module. Does manually bleeding work too. I've seen a YouTube video on bleeding the ABS via a valve on the side.

As far as I know none of the manual bleeding methods that people have described actually work 100%. I think you really need a scan tool to do this properly. Some people seem to have success using the "slam on brakes on gravel road, bleed, repeat" process, but I think I'd rather just pay to have a shop do it or buy the correct tool.
 

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Do a search for "NBS master Cylinder quick take up calipers." Schurkey and I believe L31MaxExpress have both offered some insight on the subject. There are many threads on the subject but here's one, relevant discussion starts near the bottom of page two.

https://www.gmt400.com/threads/nbs-master-cylinder-swap.51713/page-2

Also kind of off topic, but sometimes the search function on this site leaves a little to be desired. If you go to the Google home page and type (without the quotes) "site:gmt400.com NBS Master Cylinder" for example, you'll get all the results for those words from gmt400.com only. This can be a handy trick for finding info when you don't remember a thread title or location.
Thank You! I've just been googling threads about this and I always thought I wasn't getting all the results that this site could offer. I'll take a look into the link you just sent me.
 

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As far as I know none of the manual bleeding methods that people have described actually work 100%. I think you really need a scan tool to do this properly. Some people seem to have success using the "slam on brakes on gravel road, bleed, repeat" process, but I think I'd rather just pay to have a shop do it or buy the correct tool.
I've looked into the scan tool and I know deep down inside that's the right way to bleed these modules. I want to try and manually bleed the ABS module first and if all else fails, I'll just bring it to a shop.
 

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Do a search for "NBS master Cylinder quick take up calipers." Schurkey and I believe L31MaxExpress have both offered some insight on the subject. There are many threads on the subject but here's one, relevant discussion starts near the bottom of page two.

https://www.gmt400.com/threads/nbs-master-cylinder-swap.51713/page-2

Also kind of off topic, but sometimes the search function on this site leaves a little to be desired. If you go to the Google home page and type (without the quotes) "site:gmt400.com NBS Master Cylinder" for example, you'll get all the results for those words from gmt400.com only. This can be a handy trick for finding info when you don't remember a thread title or location.
I've read this thread before and I've read a little deeper since you sent me the link. I completely respect your opinion not to swap out the GMT400 MC for the GMT800 MC. However, @Schurkey has mentioned that:
IF (big IF) there are no external leaks, and IF you are not applying more pedal force once stopped...a slowly sinking pedal is classic symptom of an internally-leaking master cylinder. In other words, you need a new master cylinder that works properly.

If you are increasing pressure on the brake pedal once stopped, having the pedal sink a little bit and then hold firm is totally normal, for all the reasons given in a previous post--caliper flex, hose ballooning, seal distortion, heck, even firewall flex can make a difference in perceived pedal height. If the pedal continues to sink...the master has failed.
This is what I'm struggling with right now. This along with the particles in my brake fluid leads me to believe that the MC is failing internally along with my front brake hoses. Because I have a GMT800 MC sitting in my garage, I'll swap it out sometime in the near future and test it out for myself. Once again, I completely understand where you and @Schurkey are coming from and I only have myself to blame if it doesn't end well. If the swap fails, I'll just buy a new GMT400 MC.
 

df2x4

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This is what I'm struggling with right now. This along with the particles in my brake fluid leads me to believe that the MC is failing internally along with my front brake hoses.

If the pedal keeps sinking as you hold it down, then yes I'd say your MC is definitely failing.
 
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