GMT900 front brake upgrade for my GMT821 ... what ELSE do I need?

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Marky Dissod

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If it were a Suburban, or I towed / hauled very heavy / aerodynamically draggy things, I'd HydroBoost it.
Since it's mostly me and 3 or 4 more, I'll start investing in GMT900 front brake kit parts now.

Where do I get a good set of (5?) braided stainless steel brake lines?
 

Sam Harris

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If you've got Hydroboost, seals in that are known to go out. There's a rebuild kit or you can get a reman unit.
If it were a Suburban, or I towed / hauled very heavy / aerodynamically draggy things, I'd HydroBoost it.
Since it's mostly me and 3 or 4 more, I'll start investing in GMT900 front brake kit parts now.

Where do I get a good set of (5?) braided stainless steel brake lines?
I used the Goodridge kit. However, the middle line in rear that splits the two sides had a fault, where the line wouldn’t seat deep enough into the bracket / splitter, so I had to have a new one fabbed. They are aware of the issue, and most / all of the newer kits are correct. I’ll try to find the part number.

ETA: Goodridge part: 14175, for the 5-line (non Stabilitrak) kit.
 

corvette744

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I don’t have hydroboost (unfortunately), and the conversion is a bit of a PITA, though not too bad. But after the GMT900 upgrade up front, stainless lines in all 5 locations, and the Powerstop Z36 on all four corners, it’s a dramatic improvement! If I had the hydroboost as well, that would be some serious braking force.
Anyway. As far as I’m concerned, the GMT900 upgrade, combined with stainless lines, and good rotors & pads is more than adequate.
Agreed big improvement over stock setup no even close.The stainless lines will make the brake pedal feel alot stronger then stock flexible hoses.If you really want to see the difference do the calipers -rotors and pads.Drive it 500 miles.Then do the stainless lines and you will see what im talking about-tops off a great upgrade.
 
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Marky Dissod

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So I got stymied when I went to
and realized that I don't think selecting
'Caliper Bracket'
is possible.

If 'Caliper Bracket' cannot be selected, what should I select so I get a pair of caliper brackets?

Except for the caliper brackets (whatever car-part.com wants to call them), I want to buy everything new.
If the cost of used caliper brackets is too close to new, though, then I'll just buy everything new.
 

Sam Harris

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So I got stymied when I went to
and realized that I don't think selecting
'Caliper Bracket'
is possible.

If 'Caliper Bracket' cannot be selected, what should I select so I get a pair of caliper brackets?

Except for the caliper brackets (whatever car-part.com wants to call them), I want to buy everything new.
If the cost of used caliper brackets is too close to new, though, then I'll just buy everything new.
The calipers should come with the brackets. Do the parts you’re ordering have pictures of the setup?
 

petethepug

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Check RockAuto. I looked under 09 Esky and a new OEM GM L or R caliper was $62.89. Brackets were a little pricey @ $25 ea but you can always take the part #’s and scour the internet for a better deal.

I forgot to look, the Raybestos calipers, semi loaded w/ the brackets were $75 ea. Don’t forget the 5% discount code in the R/A vendor section.
 

adriver

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You also need to have minimum 17" wheels.

EDIT: So IF YOU ARE ON 16s NOW, and need to upgrade those too, you NEED TO reevaluate doing the 2020+ 4 piston calipers. Those require at least an 18" wheel, and not all 18" wheels will fit. Those are a better caliper and if you are buying everything to do it anyways, then you aren't spending that much more, and you will want to just do it once. I'm not telling you to do it, but you do want to spend the time to price em both out, see what kind of wheels you want to have, and compare your two overall options. If you don't have the wheels yet, then what you need to get is to similar to not be aware of your options before you start buying parts.

If you need to do the wheels (which is also tires), that's the biggest cost of this. If that's not immediately in the budget, then I would highly recommend the hydroboost swap. It will definitely improve your braking, and your overall driving experience and confidence in the mean time until you can come across a good set of take-offs, or a better time to upgrade the wheels and tires.

You could also buy new pads for $30-$50, (and make sure you have clear brake fluid) to improve what you have now.
 
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petethepug

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Good point. If you find a set of 18” rims you like now you’ve got a reason to go OEM ++
 
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Marky Dissod

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Long story short: are your front wheels at least 17"?
Get and install the following parts from a 2010 Chevy Tahoe / Yukon / Suburban / XL / Escalade (same difference), onto yours:
front caliper brackets
front calipers
front rotors
front pads

A damn good reason to upgrade to 17" or bigger wheels.
 

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