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We're looking at Jeep Grand Cherokee/Commander front brakes now. Very similar to the Trailblazer front brakes. 2 piston iron caliper and 12.9x30mm rotors. They're already 5x5 bolt pattern. The pilot bore is smaller than the stock B car, but you cut the register down when modifying the stock B rotor to a hub. There are hubcentric adapters available off the shelf to return the wheel to hubcentric. The rotor isn't quite as thick as the Corvette, but once the hub modifications are made, it's bolt on. Rotors are relatively cheap, and there's a wide selection of performance pads available.

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Are you talking about the SRT brakes?

I'm very interested in budget big brake options for those of us who are not limited to 15" rims. The SRT calipers and the Trailblazer EXT calipers both look pretty nice. I just don't have the technical knowledge to figure out fitment.

EDIT: My friend says the 1st gen SRT calipers are the same as the CTS-V calipers. It would be pretty sweet if they bolted up to b-body brackets.
 

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Are you talking about the SRT brakes?

I'm very interested in budget big brake options for those of us who are not limited to 15" rims. The SRT calipers and the Trailblazer EXT calipers both look pretty nice. I just don't have the technical knowledge to figure out fitment.

EDIT: My friend says the 1st gen SRT calipers are the same as the CTS-V calipers. It would be pretty sweet if they bolted up to b-body brackets.
Possibly the SRT stuff could be made to fit. I'm just talking about the regular stuff though. The caliper adapter brackets might be a challenge, me and another MISSL guy have been working in this for a while. FWIW, the stock rotors and calipers work pretty well with a good pad. We have been using them while road-racing our LeMons Caprice. We have run a full 8-hour day on a single set of front pads with life left in them. We're upgrading fronts and rears using Jeep parts, but it's not bolt on. The stock GC/Commander brakes upgrade you from a 11.9x1" (most say 12, they come in a little under) to 12.9x1.125 and a nice, stiff 2 piston iron caliper. For thermal fatigue, I'll take iron calipers any day over even C6 calipers. Aluminum starts to get soft after hours of abuse and you start seeing radial taper wear in the pads . We're looking at both the Trailblazer and the GC caliper right now. They are very similar, but the caliper bracket mounting looks a little more favorable on the GC calipers.

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Reach out to Jason Hurst on Facebook - he offers Brembo brackets for the GM "tall" knuckle used on B-body. Not sure what his name is on ISSF, Extreme something, related to his history with S10 Extreme pickups, I think. Sells on ebay.
 

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Possibly the SRT stuff could be made to fit. I'm just talking about the regular stuff though. The caliper adapter brackets might be a challenge, me and another MISSL guy have been working in this for a while. FWIW, the stock rotors and calipers work pretty well with a good pad. We have been using them while road-racing our LeMons Caprice. We have run a full 8-hour day on a single set of front pads with life left in them. We're upgrading fronts and rears using Jeep parts, but it's not bolt on. The stock GC/Commander brakes upgrade you from a 11.9x1" (most say 12, they come in a little under) to 12.9x1.125 and a nice, stiff 2 piston iron caliper. For thermal fatigue, I'll take iron calipers any day over even C6 calipers. Aluminum starts to get soft after hours of abuse and you start seeing radial taper wear in the pads . We're looking at both the Trailblazer and the GC caliper right now. They are very similar, but the caliper bracket mounting looks a little more favorable on the GC calipers.

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Michael, while I assume you're talking about using 17" Impala SS wheels, there is another rotor/caliper combination that might be of interest - Cadillac used the same 345 x 30 rotor from PPV on the CTS V6 (RPO J55), with a 2-piston floating iron caliper. Even the PPV single-piston floating iron caliper could work pretty well, but in both cases, I believe it will necessitate 18" wheels....but maybe adapting PPV 18x8 steel wheels to the Lemons car wouldn't be such a bad move to stuff in relatively inexpensive bigger brakes, and tire choices in 18" are better, I believe. The wheels are high-offset, so there's room for a proper adapter or hub/spacer with LONG studs (14mm) - 120mm pattern. Long 14mm studs are offered by SwayAWay - up to 100mm - Wheel Studs - Sway-A-Way | Racing Technology
 

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Michael, while I assume you're talking about using 17" Impala SS wheels, there is another rotor/caliper combination that might be of interest - Cadillac used the same 345 x 30 rotor from PPV on the CTS V6 (RPO J55), with a 2-piston floating iron caliper. Even the PPV single-piston floating iron caliper could work pretty well, but in both cases, I believe it will necessitate 18" wheels....but maybe adapting PPV 18x8 steel wheels to the Lemons car wouldn't be such a bad move to stuff in relatively inexpensive bigger brakes, and tire choices in 18" are better, I believe. The wheels are high-offset, so there's room for a proper adapter or hub/spacer with LONG studs (14mm) - 120mm pattern. Long 14mm studs are offered by SwayAWay - up to 100mm - Wheel Studs - Sway-A-Way | Racing Technology
Aside from the wheel size issue, what other obstacles exist? Do these calipers bolt on? What needs to be done to get everything to line up laterally?
 

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Michael, while I assume you're talking about using 17" Impala SS wheels, there is another rotor/caliper combination that might be of interest - Cadillac used the same 345 x 30 rotor from PPV on the CTS V6 (RPO J55), with a 2-piston floating iron caliper. Even the PPV single-piston floating iron caliper could work pretty well, but in both cases, I believe it will necessitate 18" wheels....but maybe adapting PPV 18x8 steel wheels to the Lemons car wouldn't be such a bad move to stuff in relatively inexpensive bigger brakes, and tire choices in 18" are better, I believe. The wheels are high-offset, so there's room for a proper adapter or hub/spacer with LONG studs (14mm) - 120mm pattern. Long 14mm studs are offered by SwayAWay - up to 100mm - Wheel Studs - Sway-A-Way | Racing Technology
We have a ton of 17" SS wheels, but I am intrigued on the extra rotor diameter. The rotor would need to be redrilled though, and I lose the off-shelf bolt on nature of the rotors. With the GC design, the hub register is modified to fit the smaller I'd of the rotor bore, so once the hub is modified (with spares in case we kill a bearing) the rotor is available at most auto parts stores.

Once we are done modifying the front knuckles, and rear axle shafts, there's nothing that keeps us from buying auto parts store brake parts in a pinch. Though we travel with at least 1 spare set of rotors, pads and front bearings, you never know when we might still need to hit the auto parts store.

The SRT GC rotor is 360mm, so way that will fit with an tall-bridge iron caliper.

We're limited to a 190 treadwear tire, and. 275ish 17" tire is about $50+/tire less than a 265,275,or 285 section width 18" tire in 30/35/40 aspect ratios. $50/tire makes a difference when we eat at least 1 set in a 15 hour race.

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For REAR 15 stock rims think take parts :
E-brake TRW Calipers BHS331 + BHS330 - this from VW T5, 41mm cylinder
Brake Pads Support — BDA632 2pcs TRW
Brake Pads — GDB1516 TRW
Disks — 6060052 Girling, they 300mm diameter, 22mm thick. maybe 300mm is overziesed... do not know.
And ... make backing plate for this capers...

Anybody can find rotots by size here (EUROPE):
Каталог тормозных изделий Brembo предназначен экспертам по запасным частям

Calipers have e-brake system allready!

Interesting posts for this calipers and disks here:
Тормоза S4 (345мм перед, 300мм зад) — Audi A4, 2.0 л., 2005 года на DRIVE2
Нужно больше тормозоов😬 — Audi A4, 2.8 л., 2000 года на DRIVE2
 

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I just thought of something...

Back when I was looking into budget rear brake options, I found out that the rear calipers on the b-body can be interchanged with those on a 4WD S-10, as the mounting holes are the same. With that in mind, what are the chances that the dual-piston front calipers from those S-10's and Blazer's would bolt up to our front mounting holes? Those calipers are dirt cheap.
 

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The rotor size is still the point - the twin piston caliper on S10 Blazer sits on a rotor that is 10.8" diameter, even though it's 1.14" thick, which is a little more than stock - still not to the level of the Astro Van option - which is both thicker & larger in diameter compared to Blazer. The smaller rotor also means that the pad arc is tighter - mounting to a larger rotor, if one can be found with the proper thickness, diameter, hat height, etc. would be a compromise as far as pad contact & brake torque production. There is no real magic in a multi-piston caliper until you move to a fixed vs floating setup.
 

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We looked at using the 2003-up 2WD Astro knuckle with the conventional balljoint mounts, which is a great candidate for a B-body big brake setup because the caliper mounting points do not constrain rotor diameter, one of the biggest drawbacks of the stock B-car knuckle.

The problem we ran into is that the 2003-up 2WD Astro hub is 6x5.5" bolt pattern which puts you in a different category for rim choice, and the track width is significantly wider. We were really trying to keep the 5x5" bolt pattern.
A couple questions:

1.) Let's assume that the factory Astro rims are my all-time favorite wheels, so bolt pattern isn't an issue. How significant is the track width increase? How does it compare to the increase you create by putting a set of rotors over your old hats?

2.) Any chance the hubs from either the Trailblazer or earlier Blazer/S-10 would bolt up to that Astro knuckle? Again, let's assume bolt pattern is not a concern. What about the f-body hub?
 

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Just some more thoughts as I wait for more knowledgeable people to chime in:

Since the 2003+ 2WD Astro uses the same 6 x 5.5 bolt pattern as the full-size trucks, people such as myself and 96 Black could potentially bolt the 3rd gen Escalade wheels that we like so much directly on to our Fleetwoods. It would also open up a whole new class of wheels that are generally larger, more common, and possibly more affordable than our 5 x 5 options. Additionally, if the S-10 hubs use the same 3-bolt pattern as the Astro, that would be an option for people who want to run Corvette rims/brakes, or any other parts in that 5 x 4.75 class.

If you can't tell, I very much like the idea of converting to a bolt-on hub with a separate rotor, as it is the more modern design. I would love to come up with a combination of OEM parts that fit together without modification.

There are a few rotors I came across that use the 6 x 5.5 bolt pattern. The 3rd gen Escalade uses a 13.0" rotor in that size. The 2008 Lexus GX470 uses a 13.3" inch front rotor, and the 2008 Nissan Armada is almost 13.8". All are dirt cheap.
 

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A couple questions:
. What about the f-body hub?
Just some more thoughts as I wait for more knowledgeable people to chime in:

Since the 2003+ 2WD Astro uses the same 6 x 5.5 bolt pattern as the full-size trucks, people such as myself and 96 Black could potentially bolt the 3rd gen Escalade wheels that we like so much directly on to our Fleetwoods. It would also open up a whole new class of wheels that are generally larger, more common, and possibly more affordable than our 5 x 5 options. Additionally, if the S-10 hubs use the same 3-bolt pattern as the Astro, that would be an option for people who want to run Corvette rims/brakes, or any other parts in that 5 x 4.75 class.

If you can't tell, I very much like the idea of converting to a bolt-on hub with a separate rotor, as it is the more modern design. I would love to come up with a combination of OEM parts that fit together without modification.

There are a few rotors I came across that use the 6 x 5.5 bolt pattern. The 3rd gen Escalade uses a 13.0" rotor in that size. The 2008 Lexus GX470 uses a 13.3" inch front rotor, and the 2008 Nissan Armada is almost 13.8". All are dirt cheap.
I think what you have to consider is the weight of the B/D vehicle vs the weight of the vehicle the hub/bearing unit is engineered for. That might make the Camaro or even S10 unit questionable, if there's even a way to make them fit. Further would be steering linkage - S10 is essentially the same as the "metric" Malibu/Monte Carlo chassis, which is a scaled-down version of the B/D, both front steer. No matter which platform, the unitized hub/bearing is generally used with relatively high-offset wheels (compared to B/D) - even Astro and later 6-lug trucks. The idea was to make room for larger brakes as the wheel size grew, brake performance became more demanding, and service intervals for things like wheel bearings was targeted for elimination--NVH engineers wanted to eliminate the variability that could come with such things as bearings that were "adjustable"--the "lubed for life" concept.
 

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Bill... While we are on the subject... Do you know what other axle shafts might interchange with ours? Assuming I change the front bolt pattern, obviously the next step would be the rear.
 

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Bill... While we are on the subject... Do you know what other axle shafts might interchange with ours? Assuming I change the front bolt pattern, obviously the next step would be the rear.
I'm not Bill, but I did stay at a Holiday Inn Express last night :)

I've been considering this same thing for the same reasons (6x5.5 wheels). A lot of trucks came with 8.5" 10 bolts, but there are several versions of this rear end. Wagons have the larger axle bearings so they might be compatible with the truck axles in diameter, but I'm not sure about length or spline count.

I'm guessing that one would need wheel spacers to make a "flush" wheel fit, but spacers are a lot easier than adapters from 5x5 to 6x5.5 which are a minimum of 2" thick.

 

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Bill... While we are on the subject... Do you know what other axle shafts might interchange with ours? Assuming I change the front bolt pattern, obviously the next step would be the rear.
No idea - the mix of bearing/journal size, spline count, flange to housing flange standoff, shaft length, flange diameter, brake drum/disc hub register, and wheel stud pattern has too many variables. Since they're flat - which is your real concern, just have Moser make what you need.
 

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I'm not Bill, but I did stay at a Holiday Inn Express last night :)

I've been considering this same thing for the same reasons (6x5.5 wheels). A lot of trucks came with 8.5" 10 bolts, but there are several versions of this rear end. Wagons have the larger axle bearings so they might be compatible with the truck axles in diameter, but I'm not sure about length or spline count.

I'm guessing that one would need wheel spacers to make a "flush" wheel fit, but spacers are a lot easier than adapters from 5x5 to 6x5.5 which are a minimum of 2" thick.

OMG! That picture made my day.

Glad to hear I'm not the only person looking into this.

Would it make sense to re-drill the axle shafts?
 
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