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Discussion Starter #1
I had problems last year In the summer with my brakes being very weak after making a hard stop from high speeds. They would go back to normal after awhile. Yesterday I made a hard stop and while about to make a turn I had the brake pedal maxed to the floor. When I stopped safely I smelled the front brakes burning, the rear was not burning and ABS was not activated as there was not enough braking power. I replaced the front pads and rotors 2 months ago with Duralast GT pads and rotors, the best pads AutoZone has. But still the problem occurs when you make a hard stop. I'm pretty sure I need to have the brake fluid flushed as mine Is black. But wondering If anything else can cause this. Thanks.
 

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Calipers will not close properly if the fluid is bad. Surprised you are not getting an abs light on. Changing the fluid may correct the problem, but possible you may have damage to the seals.
 

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If the fluid is black it's way way way overdue for a fluid flush. Glycol brake fluid attracts water and water rusts steel and aluminum. One of the oxides of Iron is very dark... almost black.
You should flush the brakes out every 24 months to rinse out the rust and H2O contaminated brake fluid.

Flush the brakes with a pressure bleeder, do an ABS "auto bleed" with a Tech2 or similar tool, and flush the brakes again to rinse out any crud and air that gets knocked loose by running the ABS motors.
You can do this with a laptop and MDI or a Tech2. An Autel Maxicheck will do it too but it costs about the same as a good Chinese MDI clone with Tech2Win and it will not do the same things the GM tool will handle.
I'm going to post a thread on changing tire size in the ABS and PCM with some videos on Tech2 and MDI scanners.

 

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Discussion Starter #4
Yeah I checked with my favorite shop and they said $150.00 and the dealer around the corner from me said $169.00 for a flush. But Is It standard for them to activate the ABS when doing a flush? Thanks.
 

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Discussion Starter #6
Ok bringing this back Instead of creating a new one. So I did the police upgrade and bought parts for a 2012 Impala LTZ with the police package. I ordered AcDelco re-manufactured front calipers (rockauto), AutoZone GT rotors and the CMAX pads as the GT pads were not available In the police size. Anyway's braking Is 100 times better as slamming on the brakes will easily kick the ABS In. I just ordered some remaned AcDelco calipers for the rear and GT rotors and GT pads. So when the calipers get here I can Install them. Braking Is alot better I was playing with a Ford Focus ST and hit the brakes so hard that my pop flew out the cup holder and went all over the passenger floor. I haven't lost braking power as I did with the old parts yet but then that's the first time I've used them that hard. I don't smell anything burning. So Idk maybe my old calipers were not releasing and dragging causing them to heat faster. But everything Is going smooth so far. Except I still have a small problem. I flushed all 4 brake lines about a month ago and used Valvoline DOT4 and this was before the upgrade and I still lost braking power when they got hot. Reflushed the front lines again and bled them with the new calipers. But the pedal still goes about 30-40% down before actually braking. The brakes work fantastic but still that extra travel worries me. Pedal doesn't sink to the floor so Im assuming the master cylinder Is fine.
 

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You need to do an ABS bleed cycle with a bi-directional OBD-II/GM-CAN diagnostic tool.

My T400 Sierra Classic, T800 Silverado, and W-Body 09 Impala brakes will not behave properly after a brake fluid flush til I run the ABS bleed procedure. I don't introduce air into the system but the pedal doesn't sit right if I don't exercise the ABS motors with a bi-directional diag tool.
 

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Discussion Starter #8
You need to do an ABS bleed cycle with a bi-directional OBD-II/GM-CAN diagnostic tool.

My T400 Sierra Classic, T800 Silverado, and W-Body 09 Impala brakes will not behave properly after a brake fluid flush til I run the ABS bleed procedure. I don't introduce air into the system but the pedal doesn't sit right if I don't exercise the ABS motors with a bi-directional diag tool.
Ok looks like I'll be getting one of those Chinese knockoff tech 2's. Thanks.
 

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Ok looks like I'll be getting one of those Chinese knockoff tech 2's. Thanks.
Get at least one extra Linear Flash card with the latest GM North American Operations software. IIRC it's GM NAO 33.004
If you get the wrong image it's not difficult to overwrite it. My steam powered HP NX7400 laptop with PCMCIA ports can burn flash images to the Tech 2 cards. There are lots of Windows XP era Sony, Toshiba, Dell, and HP laptops with PCMCIA ports that'll work just fine for this task. Search the SAAB forums and the Tech 2 Facebook page for guidance. MMH Auto forums are another source but that's the Wild West.

This is not something you're going to use every day. I keep the Spare Cards, tool, cables, and CD ROM discs in heavy Ziploc freezer bags to limit moisture exposure.
 

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Discussion Starter #11
I was going to go that route when my pads wear out. Did you have to replace the caliper bracket too or does the SS caliper bracket work?
The factory calipers If I'm not mistaken are the same across all 8th gens except the police package. So really there's only 2 caliper types, normal and police. The SS caliper and bracket was a lot smaller than the police caliper. But was still a direct swap.
Get at least one extra Linear Flash card with the latest GM North American Operations software. IIRC it's GM NAO 33.004
If you get the wrong image it's not difficult to overwrite it. My steam powered HP NX7400 laptop with PCMCIA ports can burn flash images to the Tech 2 cards. There are lots of Windows XP era Sony, Toshiba, Dell, and HP laptops with PCMCIA ports that'll work just fine for this task. Search the SAAB forums and the Tech 2 Facebook page for guidance. MMH Auto forums are another source but that's the Wild West.

This is not something you're going to use every day. I keep the Spare Cards, tool, cables, and CD ROM discs in heavy Ziploc freezer bags to limit moisture exposure.
I actually ordered this one, If I don't like It I'll send It back and get the tech 2
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/322824891739
 

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The factory calipers If I'm not mistaken are the same across all 8th gens except the police package. So really there's only 2 caliper types, normal and police. The SS caliper and bracket was a lot smaller than the police caliper. But was still a direct swap.


I actually ordered this one, If I don't like It I'll send It back and get the tech 2
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/322824891739
Post what your experience with that tool is.
The biggies are ABS and bi-directional engine/transmission diag controls. SIR (airbags) and BCM operations may be asking a bit much.

If it works other board members have a cheaper option.
If not others know to stay away.
 

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Discussion Starter #13
Post what your experience with that tool is.
The biggies are ABS and bi-directional engine/transmission diag controls. SIR (airbags) and BCM operations may be asking a bit much.

If it works other board members have a cheaper option.
If not others know to stay away.
Will do, says It will be here Tuesday.
 

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Discussion Starter #14
UPDATE...Got It Monday and got everything set up but couldn't actually find Impala In It. Played with It today and got It to work. ABS bleed function Is In there so I'll do that hopefully this week. There's a lot of bi-directional controls In there. My favorite Is you can make It go Into 4CYL MODE while Idling. It's for testing obviously but still. Other than that got my rear calipers, rotors and pads on. Thing stops on a dime but still has the Initial pedal travel. So I'll be bleeding hopefully this week and getting a DOT 4 cap and possibly a new reservoir as mines all black Inside.
 
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