330mm Brake caliper comparison

mopar-banshee · October 31, 2022

Hi guys.

has anyone yet compared the rear 2-piston aluminum calipers with the front 330mm brake iron ones?
To me, it makes no sense why GM did not use Aluminum calipers in front as well.

I assume that the caliper bracket does not interchange, but the caliper itself might.
Here in germany it is pretty difficult to get a hold on measurements, but I have the 330mm rear brakes installed in my Silverado.

So if noone has done the comparison yet, maybe someone with a rear drum brake Silverado can give me some measurenents of his front calipers.
The most critical are:

- spacing between the two slider bolts

- distance between the outer area where the brake pad sits against and the area the slider bolt sits against

thanks

swathdiver · October 31, 2022

Cast Iron handles the heat better than aluminum. You'd have a lot of expansion with aluminum up front and that could cause the seals to leak and the pistons to get loose and jam in their bores.

newdude · October 31, 2022

1 hour ago, mopar-banshee said:

Hi guys.

has anyone yet compared the rear 2-piston aluminum calipers with the front 330mm brake iron ones?
To me, it makes no sense why GM did not use Aluminum calipers in front as well.

I assume that the caliper bracket does not interchange, but the caliper itself might.
Here in germany it is pretty difficult to get a hold on measurements, but I have the 330mm rear brakes installed in my Silverado.

So if noone has done the comparison yet, maybe someone with a rear drum brake Silverado can give me some measurenents of his front calipers.
The most critical are:

- spacing between the two slider bolts

- distance between the outer area where the brake pad sits against and the area the slider bolt sits against

thanks

What exactly are you trying to figure out? Are you trying to upgrade the rear brakes in some sort of fashion?

mopar-banshee · November 7, 2022

@swathdiver I do not think this will be a problem.

Yes, Aluminum expands more with heat, but Aluminum also dissipates heat much faster. Most High Performance brakes, designed for high temperatures use aluminum calipers.

@newdude: I want to Upgrade the front brakes on my 2000 silverado. I have already upgraded the rear ones to the 330mm suburban ones.

The calipers in back are made of aluminum, but the 330mm front brakes use iron calipers. I want to adapt the aluminum calipers to the front brakes.

swathdiver · November 7, 2022

On 10/31/2022 at 3:06 PM, mopar-banshee said:

Hi guys...

I just realized that you are in Germany. Brembo in Europe sells 6 and 8 piston front calipers and 4 piston rear calipers for GMT900s. All use 2 piece rotors.

newdude · November 8, 2022

17 hours ago, mopar-banshee said:

@swathdiver I do not think this will be a problem.

Yes, Aluminum expands more with heat, but Aluminum also dissipates heat much faster. Most High Performance brakes, designed for high temperatures use aluminum calipers.

@newdude: I want to Upgrade the front brakes on my 2000 silverado. I have already upgraded the rear ones to the 330mm suburban ones.

The calipers in back are made of aluminum, but the 330mm front brakes use iron calipers. I want to adapt the aluminum calipers to the front brakes.

Gotcha.

None of the fronts that I recall are aluminum from any year for factory calipers. All cast iron.

If you want bigger factory brakes, you can use the ones from a 2007-2013 truck. You need the pads, calipers and rotors. You may have to modify the backing plate slightly or replace it with the newer one. You will also need to upgrade to a 17 inch wheel to clear these.

mopar-banshee · November 10, 2022

Thanks for the Input, but both of you have not really contributed anything new for me, or the measurements i specifically asked for.

@swathdiver: we have pretty strict regulations (TÜV), I am aware of the Brembo Option, but ist is not realistic in several ways.

@newdudeI know that all the front calipers from GM are iron, that ist why I asked for measurements to use the rear ones. I Run 8.5x18 oem wheels from the 2kxx Chassis.

I upgraded the rear brakes to the 330mm dual piston ones from the suburban (These calipers are aluminum).

I also checked clearance of the 4-pot ones from the 2019 silverado, but they do not fit my wheels, and the spacers that would be necessary are not TÜV legal.

So I want to use the 330mm Rotors from the rear drum Brake gmt800 silverados, but will try to negate the weight Penalty by using the aluminum calipers.

I am a trained mechanic with two decades of experience with american vehicles, racing, modification and Restoration.

Unfortunately there ist very Limited Access to parts and relevant information in Germany.

newdude · November 10, 2022

7 hours ago, mopar-banshee said:

Thanks for the Input, but both of you have not really contributed anything new for me, or the measurements i specifically asked for.

@swathdiver: we have pretty strict regulations (TÜV), I am aware of the Brembo Option, but ist is not realistic in several ways.

@newdudeI know that all the front calipers from GM are iron, that ist why I asked for measurements to use the rear ones. I Run 8.5x18 oem wheels from the 2kxx Chassis.

I upgraded the rear brakes to the 330mm dual piston ones from the suburban (These calipers are aluminum).

I also checked clearance of the 4-pot ones from the 2019 silverado, but they do not fit my wheels, and the spacers that would be necessary are not TÜV legal.

So I want to use the 330mm Rotors from the rear drum Brake gmt800 silverados, but will try to negate the weight Penalty by using the aluminum calipers.

I am a trained mechanic with two decades of experience with american vehicles, racing, modification and Restoration.

Unfortunately there ist very Limited Access to parts and relevant information in Germany.

By using rear calipers on the front? That won't work. They won't fit.

To use the larger front OE rotors, you need the matching front OE calipers.

Edited November 10, 2022 by newdude

mopar-banshee · November 10, 2022

4 hours ago, newdude said:

By using rear calipers on the front? That won't work. They won't fit.

To use the larger front OE rotors, you need the matching front OE calipers.

Have you tried?
The rotor diameter and thickmess are the same, as is the basic construction of both calipers.
To get the bracket to fit would be lucky, but to mount the aluminum caliper to the sliders of the iron front bracket might be doable.

That is why I need the measurement of the oem iron bracket for the big brake.

mopar-banshee · June 27, 2023

Update on my Front-Brake Upgrade.

Am Have bought some parts in the US and tinkered with solutions.

As of now, I should be able to adapt the rear aluminium caliper and bracket to the front Knuckle and match them up with 14,88" Rotors from a 2020 Dodge Ram.

This Idea came to me, because the brackets for the rear calipers space the caliper a lot forther out, and the additional rotor diameter would even out the lesser brake pressure due to the smaller pistons in the aluminium brake.

I will have to get Adaperts CNCed that bolt to the Knuckle and the caliper bolts to.

Because the bolt spacing is so much closer on the caliper bracket, than on the Knuckle that should work just fine.

ATM I am waiting on a Rotor to get things going.

Also I am checking to make the Aluminum Knuckles of a 2015 Silverado work on my RWD GMT800.
Geometrically they appear to be spot-on.

I will have to fabricate shims for the ball joints (taper angle matches, the aluminum Knuckle just has bigger holes.
And adapt the tie-rod-ends a bit.

At first I thought of using the inner ones also (they are beefier), but I am not sure if it is too much of a hassle, for no noticeable benefit.

I will keep you posted, and maybe I start selling the brake-Adapters