98 Z-71 spongy brakes, might've found a fix, suggestions???

[flair666369]

Hello all, I have a 98 Z-71 that I bought not too long ago, i noticed the brake feel sucks, really spongy. I've talked to many brake repair specialists, most of them told me that all trucks like mine feel the same. They told me that big brake kits will fix the problem(but are really expensive), but one mechanic who seemed to know what he's talking about told me that the real problem lays in GM's master cylinder. Since then I've been looking on the net for parts/prices. I recently found something new on SSBC's website. It's a master cylinder(part# A0463 $250.00) that claims to fix the spongy feel. Does anyone know the real cause of this problem or has installed big brake kits or a better master cylinder? If I'm going to spend the money, I want to make sure that this really fixes the problem. Any info would help, THANKS!!!

[v10_viper]

Originally Posted by flair666369

Hello all, I have a 98 Z-71 that I bought not too long ago, i noticed the brake feel sucks, really spongy. I've talked to many brake repair specialists, most of them told me that all trucks like mine feel the same. They told me that big brake kits will fix the problem(but are really expensive), but one mechanic who seemed to know what he's talking about told me that the real problem lays in GM's master cylinder. Since then I've been looking on the net for parts/prices. I recently found something new on SSBC's website. It's a master cylinder(part# A0463 $250.00) that claims to fix the spongy feel. Does anyone know the real cause of this problem or has installed big brake kits or a better master cylinder? If I'm going to spend the money, I want to make sure that this really fixes the problem. Any info would help, THANKS!!!

I'd take his word on the master cylinder, it makes sense to me. Also, go ahead and upgrade at least your front lines to stainless steel, no flex at all in those, compared to oem rubber lines, I'm not saying your lines are flexing causing that spongey feeling but they do flex a little, takes a lot to slow these trucks down. I know my dad's 99 has rubber lines up front and he has no sphongey feeling at all, so it sounds to me like the master cylinder could really be the culprit. Nothing at all wrong, some people like brakes firm feeling, some don't. IF 250 bucks isn't any problem for you to spend just for the feeling then go ahead and do it, I know if I had the money I would.

[fergymoto]

So did you end up trying this? Did it work?

[Tall]

My problem was the ABS Dump Valve....

[flair666369]

Haven't tried it yet, not on uncle sam's paycheck and a truck payment, but after iraq is the plan.

[Chevy-SS]

What is the "ABS dump valve"?

Has anyone else had any luck fixing a spongy brake pedal?

I have bled the living crap out of my 98 Sily 1500 brakes and the pedal is still too soft. I really feel that this is hurting my ability to stop.

[MyTOY]

I also have a spongy brake and have bled the brakes
without much diff. My understanding is that you should
really go somewhere that has the equipment to cycle
the ABS when bleeding. I'm not sure what this equipment
is but my local Monroe shop that did some brake work
for me didn't have it. I am also curious about the dump valve
that I've heard a little about before. Did it need replacing
or bleeding or what? Thanks

[70camaro]

I belive the type of brake pad also makes a difference. Go with the high end ones. I cant remember what they're made of.