Particles in the brake fluid

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Schurkey

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It's crazy to use a two-chamber master cylinder when you have low-drag front calipers on that 1500.

Those calipers were designed and intended to use with a three-chamber Quick Take-Up master cylinder. There's also the potential issue of the caliper pistons being "sticky" in the bores. Really common. Not outright seized, but requiring more fluid pressure to move than they should. Same deal for the caliper mounting sleeves and rubber insulators--the calipers need to "float" freely on the guides, not be stiff 'n' sticky.

Leave the GMT800 master cylinder in the garage, get the RIGHT master cylinder for your truck.

Remember, the rear brakes are the usual problem with 1500s. Out of adjustment, poor design. Upgrading to the 11.x Duo-Servo rear brakes is a wonderful thing.

I tried bleeding the ABS in my '97 by pushing the lil' buttons on the combo valve. I got nothin'. You're going to need a scan tool to bleed the ABS properly.
 

Boots97

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It's crazy to use a two-chamber master cylinder when you have low-drag front calipers on that 1500.

Those calipers were designed and intended to use with a three-chamber Quick Take-Up master cylinder. There's also the potential issue of the caliper pistons being "sticky" in the bores. Really common. Not outright seized, but requiring more fluid pressure to move than they should. Same deal for the caliper mounting sleeves and rubber insulators--the calipers need to "float" freely on the guides, not be stiff 'n' sticky.

Leave the GMT800 master cylinder in the garage, get the RIGHT master cylinder for your truck.

Remember, the rear brakes are the usual problem with 1500s. Out of adjustment, poor design. Upgrading to the 11.x Duo-Servo rear brakes is a wonderful thing.

I tried bleeding the ABS in my '97 by pushing the lil' buttons on the combo valve. I got nothin'. You're going to need a scan tool to bleed the ABS properly.

Like I said earlier, I completely respect your opinion on why you don't want to use a GMT800 MC on your 400. I also know that manually bleeding the ABS Module isn't the correct way to bleed these modules. However, because I already have the GMT800 MC and I'm pretty sure my original MC is failing, I may as well try it out. A lot of people have done this mod and are overall very happy with it. I also want to see if I can get lucky and bleed the ABS module manually and see if my brakes get better. If all else fails, I'll just buy a new GMT400 MC and go to a shop and have them bleed the module for me. I know it sounds like a waste of time, but at least I'm learning along the way.
 

Caman96

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If everything else is being replaced, why not new calipers?
 

Caman96

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This would be a great time to upgrade to braided stainless brake lines instead of the factory rubber lines. It'll eliminate some slop from your brake pedal feel. I used a kit from Russell on my red '97, but IIRC there's an even better kit available from some other company. I'll try and find it here in a bit.
@df2x4 just curious how noticeable a difference using SS hoses?
 

df2x4

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@df2x4 just curious how noticeable a difference using SS hoses?

Hard to say as I did everything I could think of at the same time, right down to the fancy Wilwood brake fluid. The difference it all made was pretty incredible though. My dad bought that truck new and he says it's never stopped this well before.

EDIT - To clarify a little, I also had the ABS module bled while this was all being done. There was a pretty big difference in pedal feel but I'm not sure if the ABS bleed or the hoses had the largest effect.
 

Caman96

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That’s the thing though, you did it right doing it ALL, as it is a system and doing it partially doesn’t complete. When I got my truck 3 years ago with only 46k, I did everything except bleeding ABS and SS hoses. Brakes feel great, maybe there was no air in module though. But, I can’t imagine doing ABS bleed and new SS hoses wouldn’t improve though.
 

df2x4

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The only original parts left in the brake system of that truck are the MC, booster, hard lines and ABS module. They're all still doing OK, unless you count the mildly hilarious coating of surface rust on the booster.
 

Alteca

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I can agree with the others, the NBS master isn’t the best idea if it’s the 1.34” bore. That’s the one I’m currently running and the pedal travel is amazing but the panic stops can be scary. I’m about to swap to the smaller 1.25” bore that some NBS trucks used which should help. I’m not using quick take up calipers so I can’t speak on how that will work. I have also tested braided lines vs stock and it’s not a massive change but there is some improvement under heavy braking, the pedal just has a bit less give to it. Could have also been from brakes being properly bled after the swap as well.
 

Schurkey

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I've been hearing about steel-braid-over-Teflon (PTFE) liner brake hoses since about 1984 or so.

EVERYONE says they produce a much-firmer pedal with less travel than "squishy" OEM Rubber hoses.

Yeah, OK. "I" have not noticed a big difference. I do think the service-life with the Teflon hoses should be longer than the fabric-reinforced rubber hoses.

I don't doubt that they produce a firmer pedal than ancient, worn-out fabric-reinforced rubber hoses that have a zillion miles on them already. Whether they produce a firmer pedal than new fabric/rubber hoses is questionable. Sort of like fabric-reinforced rubber rag joints in the steering that get sloppy with age and use, while new ones are appropriately stiff.

All that said...I've got steel-braid-over-Teflon (PTFE) liner brake hoses on most of my vehicles. I don't replace good rubber hoses with the Teflon stuff, but if the hoses need replacement anyway, I generally spring for the hot-roddy hoses. I've even developed Teflon brake hoses for unpopular cars that didn't have aftermarket brake hose kits--using "universal" brake hoses plus adapters and fittings as needed to make 'em work on a '66 Toronado, and '92 and '93 Luminas. I've even bought so-called exact-fit "replacement" Teflon hoses from Famous Names that didn't fit worth a crap because the manufacturer screwed-up the length or the hose diameter, or cheapened-out on the design by eliminating hard-tube sections.

Yes, the Classic Tube StopFlex SBH6055 seem to be the way to go, when I need hoses on my '97 K2500, that's what I'll be ordering.
www.summitracing.com/parts/cst-sbh6055
 

Boots97

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If everything else is being replaced, why not new calipers?
I don't want to replace things that are still good. The only reason why I replaced the rear hose is bc I knew it would be a PITA to replace later so I thought I may as well replace it now. I also replaced the wheel cylinders bc I broke the body of one of the wheel cylinders while reinstalling a new bleeder screw. The drums are stupid simple so I just replaced both sides as well.
 
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