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Old 01-21-2019, 05:37 PM   #176
speedygonzales
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Why do you have to do it?

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Originally Posted by hb32 View Post
Thanks for the info. Unfortunately I donít have a scanner so looking at alternative methods. I just took it for a drive and it is noticeably different then yesterday, after slamming on the brakes to activate the ABS. Will try that a couple more times and bleed again.
Activating the ABS is NOT the same thing.

Why can't you just take your vehicle to a small local garage to get it done?

The procedure says to bleed like normal, do an automatic bleed then bleed like normal one last time.

A small time shop should not charge more than $50+- to do it.
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Old 01-24-2019, 05:13 PM   #177
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Re: First hand experience with changing to the NBS master cylinder WOW!

Has gotten considerably as well as noticeably better.
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Old 01-24-2019, 05:20 PM   #178
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Re: First hand experience with changing to the NBS master cylinder WOW!

Has anyone actually done empirically accurate 60-0 and 100-0 testing before/after the NBS master cylinder swap? Because when I did the swap on my '99 Tahoe, extensive testing with my G-Force meter showed that braking distances actually got WORSE. Needless to say, I went back to the original master.
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Old 01-24-2019, 05:34 PM   #179
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Re: First hand experience with changing to the NBS master cylinder WOW!

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Originally Posted by z71se View Post
Has anyone actually done empirically accurate 60-0 and 100-0 testing before/after the NBS master cylinder swap? Because when I did the swap on my '99 Tahoe, extensive testing with my G-Force meter showed that braking distances actually got WORSE. Needless to say, I went back to the original master.
Interesting 🤔
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Old 01-24-2019, 05:37 PM   #180
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Re: First hand experience with changing to the NBS master cylinder WOW!

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Interesting 🤔
The fact that it improves the braking FEEL especially when you first push the pedal is indisputable. However, where is the discussion regarding the fact that a disc/ disc master is being installed on disc/ drum cars with different weight distribution and no one thought to actually measure pressures at each individual wheel as well as do apples to apples brake testing?
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Old 01-28-2019, 10:53 AM   #181
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Yeah right............

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Originally Posted by z71se View Post
Has anyone actually done empirically accurate 60-0 and 100-0 testing before/after the NBS master cylinder swap? Because when I did the swap on my '99 Tahoe, extensive testing with my G-Force meter showed that braking distances actually got WORSE. Needless to say, I went back to the original master.
With your "empirically" accurate leg pressure?

Did you ever do the "automatic bleed" procedure?

A drum system uses significantly less pressure then a disc system. Not sure if I even believe that changing the rear drum system to the pressure of a disc system would have a negative effect. Maybe the front system pressure goes down after the swap. Doesn't concern me.

Be that as it may, I rebuked this post a long time ago stating many people would gain the better feel/quality of the system by simply getting the automatic bleed done. I didn't think the ABS would have an effect on the normal feel of the brakes since under normal use, the ABS is not engaged. However after reading dozens of stories concerning the results of the automatic bleed, and after having it done it myself. I know it does have an effect.

Incidentally after having thought about this for years I have come to the conclusion that the ABS, although passive, is a restriction on the normal system. Allow me to elaborate. My son has a 1984 Sierra that obviously has NO ABS. His master cylinder is the same one that came on my GMT400 from the factory. He has tremendous pedal feel and incredible stopping power that I can't even get used to after having driven mine. And yet ours is always less than great. Even in the best of situations. Even after the automatic bleed, it's not as hard at braking as other vehicles including the Sierra.

There were 2 things I was going to do to prove this is the case (don't really give a crap currently). One thing was to measure the fluid pressure at all 4 corners of both mine and the Sierra. The second thing was to make a set of jumper tubing to go around the ABS unit in my vehicle to copy his system so to speak without ABS interfering with the hydraulic lines.

If I ever G A C in the future, I might try it. In the mean time, before anyone does any hardware changes, get an automatic bleed.

Can we now let this post die a dignified death?
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Old 02-06-2019, 11:34 PM   #182
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Re: First hand experience with changing to the NBS master cylinder WOW!

Oh, my gosh..... I now own a BEAUTIFUL 2005 Yukon XL SLT....

My wonderful '88 Sierra C2500 is now owned by a collector in Germany.

Rumor has it, it will be running propane by now.....

But, Oh, my gosh..... This thread is grown into a monster.

The brake system isn't THAT complicated......

I did the MC up-grade and no issues,,,, That was over a year ago!

Kudos to the thread starter!!!
( and all the help with answers )
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Old 01-14-2020, 05:27 PM   #183
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Re: First hand experience with changing to the NBS master cylinder WOW!

Digging up this old thread,hoping someone can help me with brake line orientation on a 99 master cylinder. I am putting the hydroboost unit from a 99 silverado in my 62, but I am unsure if the master is front port to front brake, rear to rear.
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Old 01-14-2020, 07:15 PM   #184
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Re: First hand experience with changing to the NBS master cylinder WOW!

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Digging up this old thread,hoping someone can help me with brake line orientation on a 99 master cylinder. I am putting the hydroboost unit from a 99 silverado in my 62, but I am unsure if the master is front port to front brake, rear to rear.
Your thought about "front-front / rear-rear" seems logical...
( But we are talking about GM)....

My suggestion is to just stop by a repair shop.... Good luck
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Old 01-14-2020, 07:45 PM   #185
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Re: First hand experience with changing to the NBS master cylinder WOW!

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Originally Posted by 62 mark View Post
Digging up this old thread,hoping someone can help me with brake line orientation on a 99 master cylinder. I am putting the hydroboost unit from a 99 silverado in my 62, but I am unsure if the master is front port to front brake, rear to rear.
99 probably had four wheel disc brakes so the pistons are likely the same diameter.
The 99 abs metering module took care of biasing. Not sure how the old fashioned combination valve will react.
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And please let us know if and how your repairs were successful.
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