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7/28/2014 11:40:43 AM
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Kirch
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Posted: 7/11/2012 5:44:04 PM
Just did a full replacement on all 4 corners. Pads and rotors but the paddle still feels mushie. A few questions I have for anyone with expirence working on Chevy brakes.

1st, Are the brakes self adjusting? I read they were but not to sure. Not sure if I need to use the parking brake to get the brakes to self adjust.

2nd, After replacing the pads and rotors should I go ahead and bleed the brakes? Not sure if there any sensors or what not and not to sure even how to do it. So if you have a few tips I sure could use them.

Thanks,
Kirch
SDMF_Rebel
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Posted: 7/11/2012 7:39:35 PM
[Last Edit: 7/11/2012 7:40:40 PM by SDMF_Rebel]
If you have disks all the way around, there's nothing to adjust. If you have drums in the rear, they're self adjusting; want to be sure? Try locking them up in reverse. You do not need to bleed the brakes unless you open a line. They're mushie cause they're new. If you used ceramic pads for the first time, they always feel like mush until they're hot.
Kirch
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Posted: 7/11/2012 10:11:34 PM
Well the problem is they were mushie before the brake job. Maybe it is just the shitty GM brakes. I bought the thing used and could see the pads in the rear needed to be changed. I figured after replacing the pads and rotors I wouldn't get as much travel out of the peddle. I'll have to see but there is no way this is it, they have to get better after bleeding.
spurg
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Posted: 7/11/2012 10:32:16 PM
How many miles are on it? If it's the original brake fluid then now would be a great time to change it, which will in effect also bleed your brakes. It probably looks like coffee but should be clear. Start at the wheel furthest from the master cylinder and work your way towards the master cylinder(right rear, left rear, right front then left front). Keep pumping the contaminated fluid out at each brake till it runs clear. I'm guessing there are numerous youtube videos showing the process in detail. It's alot easier with 2 people, should take less than 1 hour for the whole job. Just take your time and don't let air into the lines.

Brake fluid slowly absorbs oxygen and needs to be changed periodically. Not changing it will give a soft pedal feel as well as requiring more pedal travel since the air trapped in the fluid compresses.
Kirch
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Posted: 7/12/2012 9:46:08 AM
Ok thanks for the walk through. The Tahoe has right at 60,000 miles now. I'll try that this week end and let you know how it worked out.
zercool
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Posted: 7/13/2012 8:23:25 AM
Thanks for posting this - and the replies. I've been grumbling about the brakes on my '07 Frontier for a while now, and realized I hadn't done anything with the brake fluid ... ever.
Once order starts getting restored there's that akward moment when you have to explain why the heads of your enemies are on pikes lining your cul-de-sac. -- HullBreach
SDMF_Rebel
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Posted: 7/13/2012 12:29:19 PM
I've never known anyone who has changed their brake fluid or anyone who has ever recommended to. I'm convinced it is strictly an internet phenomenon caused by companies trying to sell more brake fluid.

If your fluid is bad it has moisture in it. If you have moisture in your lines, they WILL rot and leak. "Change" your brake fluid when you fix your broken lines.

DonofKalifornia
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Posted: 7/13/2012 6:40:28 PM
Originally Posted By SDMF_Rebel:
I've never known anyone who has changed their brake fluid or anyone who has ever recommended to. I'm convinced it is strictly an internet phenomenon caused by companies trying to sell more brake fluid.

If your fluid is bad it has moisture in it. If you have moisture in your lines, they WILL rot and leak. "Change" your brake fluid when you fix your broken lines.





Brake fluid absorbs water from the air. The moisture lowers the brake fluid boiling point from the 420 deg range to 300 degrees, at 300 degs with you brake fluid boiling you no longer have a solid brake pedal.

If you leave a cap off a can of brake fluid for 8 hours, it will be so full of moisture the boiling point is only 300 degs.

And yes brake fluid aborbs moisture while in a vehicle over a 3-4 year period.

SDMF_Rebel
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Posted: 7/13/2012 7:56:19 PM
Originally Posted By DonofKalifornia:
Originally Posted By SDMF_Rebel:
I've never known anyone who has changed their brake fluid or anyone who has ever recommended to. I'm convinced it is strictly an internet phenomenon caused by companies trying to sell more brake fluid.

If your fluid is bad it has moisture in it. If you have moisture in your lines, they WILL rot and leak. "Change" your brake fluid when you fix your broken lines.





Brake fluid absorbs water from the air. The moisture lowers the brake fluid boiling point from the 420 deg range to 300 degrees, at 300 degs with you brake fluid boiling you no longer have a solid brake pedal.

If you leave a cap off a can of brake fluid for 8 hours, it will be so full of moisture the boiling point is only 300 degs.

And yes brake fluid aborbs moisture while in a vehicle over a 3-4 year period.



Not disagreeing at all with the science behind it. I disagree with the idea of the practice. It takes a lot to boil fluid, even DOT 3; odds are the vapor wear factory rotors will warp before any fade is noticed.

Look at how many cars out there are 15+ years old, original fluid, and still have great working brakes.
rightnotleft
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Posted: 7/13/2012 11:21:28 PM
Your 2006 Tahoe has disc brakes on the front and rear- that is the only way they were built. So, they do not need to be adjusted like drum brakes, they 'self adjust' as soon as you pushed the pedal down the first few times you press the brake pedal, the caliper piston pushes out until it contacts the brake pads, which in turn contacts the rotor- viola! adjusted! Some people have always complained about the 'spongy' pedal on those C/K trucks since they were redesigned in 2000. GM tried to make a few changes during those years until 2007, when the truck was redesigned again. The newer Tahoe/Yukon (2007-2012) has a much firmer pedal feel. If you have a hydraulic brake booster, a spongy pedal can be considered normal (ask a qualified gm technician to check pedal feel). A hydraulic brake booster will have hoses running to it from the power steering pump. If you feel like your pedal is still too spongy, the first thing to do is check for a leak. Obvious checks at the calipers, hoses & lines should be easily done, however, most people don't check behind the master cylinder. A leak behind the master cylinder won't always leak on the outside of the brake booster. If you have a vacuum brake booster, you will have to take the 2 nuts off (15mm) and slide the master cylinder forward, stick something long and thin into the hole (like a screwdriver), aiming towards the bottom of inside the brake booster (use like a dipstick). If fluid is on the makeshift dipstick, your master cylinder is leaking. Normally, you do not have to bleed your brakes if just replacing pads and rotors, definitely necessary if you opened the hydraulic system at any point (cracked open a bleeder screw or line fitting). Brake lining material has no affect on pedal feel. New brake pads, no matter what they are made of, will need to seat (break in) to the new rotors. Until they do, you may have brake fade when coming to a stop the first few times braking. This will go away in a short amount of time depending on how aggressive you brake. Ideally, you want to brake with medium pressure on pedal at lower speeds (25-45 mph). Maintain constant pressure from moment you start to brake until you come to a complete stop. A few times doing this, and the pads will seat. Lastly, brake fluid does not EVER need to be changed unless it is contaminiated. It is true that air (moisture) can affect the boiling point of brake fluid, but most people don't leave the system open for significant amounts of time. Brake systems are SEALED and air doesn't just seep in. The discoloration of the fluid is NOT an indicator of the condition of the fluid. Brake fluid changes color due to heat, not moisture. Shops recommend changing brake fluid based on color as a way to make money (same with power steering fluid). Certainly, it doesn't hurt to do this as preventive maintenance, new fluid/oil in anything always works to its highest potential rather than old, degraded fluid. That being said, it is not necessary to flush your brake fluid. I am an ASE certified master tech with 20 years experience, and a GM master tech for last 14 years.