Hawk Performance Brakes for the Pontiac GTO: Which Parts Fit

By Core Brake Parts Tech Team — Circleville, OH warehouse

For the 2004-2006 Pontiac GTO, the Hawk Performance pad we carry is the HB573B.615, an HPS 5.0 rear pad set cataloged for all three model years. Up front, the part you need depends on which GTO you own, because the 2005-2006 cars got a different brake package than the 2004. Below is what fits, how the Hawk compounds differ, and what to replace alongside the pads.

Which Hawk Parts Fit the Pontiac GTO

The modern GTO was built from 2004 to 2006. Hawk dealers list the HB573 pad shape for the rear axle across all three years, and the HPS 5.0 version is the one in our catalog: the Hawk HPS 5.0 rear brake pad set HB573B.615 for the 2004-2006 GTO. It is sold as a set of four pads, which covers both rear wheels.

A note on the front pads: a Hawk dealer's fitment catalog lists the HB247 shape as the front pad for the 2005 and 2006 GTO in a full range of compounds, from HPS street pads to DTC race pads. Hawk's own product page for HB247B.575, however, lists only Corvette and Cadillac XLR applications. Because the two sources disagree, pull a front pad and compare its shape and backing plate before you order a front set. If you want a front pad that is already confirmed for your year, browse our brake pads collection by vehicle.

2004 vs 2005-2006: Why the Year Matters

The GTO's brakes were revised after the first model year. The 2005-2006 cars, which came with the 6.0L V8, were fitted with a revised brake package that includes vented rear rotors. Parts makers split their catalogs on exactly that line: rotor and pad listings for the 2005-2006 car are marked "vented rear rotors," while listings for the earlier car are marked "solid rear rotors." Rotor makers also use separate part numbers for the 2004 rear rotor and the 2005-2006 rear rotor.

What this means when you shop:

• Rear pads: The Hawk HB573 rear pad is cataloged for 2004 through 2006, so the same set covers both rear brake designs.
• Rotors: Rotors are year-specific. A 2005-2006 rotor will not fit a 2004 car, and the reverse is also true. Match the rotor to your model year and to the front or rear axle.
• Front pads: Front pads also follow the year split. Confirm the year before ordering, and check the pad shape if your car has had a brake swap. Plenty of 2004 owners have fitted the later brakes.

Hawk HPS vs HPS 5.0: Picking a Compound

HPS 5.0 is one of several Hawk street compounds. They differ in how hard they bite and in how much heat they can take. Hawk publishes these temperature ranges:

HPS 5.0 is Hawk's Ferro-Carbon compound. Hawk describes it as built for high deceleration without compromising ABS operation, with consistent release for a smooth pedal. On a car as heavy and powerful as the GTO, that extra bite and the higher heat ceiling help most on repeated hard stops: canyon roads, spirited street driving, or an occasional autocross. If your GTO is a daily driver that never sees much heat, a milder compound such as the original HPS is the gentler style of pad.

One compatibility rule applies to every Hawk compound. Hawk states its pads are designed for iron rotors and are not compatible with carbon ceramic rotors. The GTO uses iron rotors from the factory and with every common replacement, so this only matters if someone has installed an exotic rotor.

Symptoms That Say the Rear Pads Are Due

Rear pads on a front-heavy V8 car usually outlast the fronts, but they still wear out. Signs it is time:

• A steady squeal from the rear while you drive, which usually means the wear indicator is touching the rotor.
• Grinding or scraping from the rear, which means metal-to-metal contact. Stop driving on it. The rotor is being damaged.
• Friction material that looks thin through the wheel spokes, or pads that are visibly tapered from top to bottom.
• A pulsation felt through the seat rather than the steering wheel, which usually points to a warped or unevenly worn rear rotor.
• A parking brake that holds poorly. On cars with a drum-in-hat parking brake inside the rear rotor, this does not always point to the pads, but check it while the wheels are off.

What to Replace at the Same Time

New performance pads bed in best on a fresh or freshly machined rotor surface. If your rear rotors are grooved, heat-checked, or below the minimum thickness stamped on the rotor, replace them with the pads. For the 2005-2006 car, our catalog includes the DBA 4000 Series HD plain rear rotor DBA42021 and the DBA Street Series T2 slotted rear rotor. DBA rotors are sold as single rotors, so order two for the axle. You will find more options in our brake rotors collection.

Also worth doing on a car this age:

• Brake fluid: Fluid absorbs moisture over time, and that lowers its boiling point. That matters on a car pushed hard enough to need HPS 5.0 pads. Flush with the fluid type printed on the master cylinder cap.
• Brake lines: Original rubber hoses on a 2004-2006 car are old. Our catalog has the Russell stainless braided brake line kit 692320 for the 2005-2006 GTO and kit 692310 for the 2004. Braided lines firm up the pedal.
• Hardware: Replace the pad clips and anti-rattle hardware if they are corroded or bent. See our brake hardware kits.

If you want more than a pad upgrade, the rear axle of the 2004-2006 car also has a bolt-on option: the Wilwood DynaPro Radial rear big brake kit for the 2004-2006 GTO.

How Hard Is the Job?

A rear pad swap on the GTO is a reasonable driveway job for someone who has done brakes before. The basic steps: loosen the lug nuts, lift and support the car on stands, remove the wheel, unbolt the caliper, and hang it from wire so the hose is not stretched. Pull the old pads, retract the piston, fit the new pads and hardware, reinstall the caliper, and torque the bolts to the value in the factory service manual. If you are replacing the rotor, remove the caliper bracket first, then check that the parking brake is fully released before sliding the old rotor off.

Afterward, pump the pedal until it is firm before moving the car, then bed in the pads. A bedding procedure is a series of moderate stops that build heat into the pads and rotor gradually, followed by a cool-down drive without holding the brakes. A proper bed-in lays down an even transfer layer. That is what gives a performance compound its consistent bite and prevents early vibration.

Frequently Asked Questions

Does the Hawk HB573B.615 fit a 2004 GTO?

Yes. The HB573 rear pad is cataloged for the 2004, 2005 and 2006 Pontiac GTO, so the same rear set fits all three years.

Is HPS 5.0 too aggressive for a daily-driven GTO?

It is a street compound and works from cold, with a published optimal range starting at 100 F. It has more bite than the original HPS. If you want the smoothest pad and rarely brake hard, a milder street compound is the gentler option.

Will Hawk pads work with slotted or drilled rotors?

Yes. Hawk pads are designed for iron rotors, and slotted, drilled and plain iron rotors are all iron. The only rotors Hawk rules out are carbon ceramic rotors.

Can I use 2005-2006 rotors on my 2004 GTO?

Not as a direct swap. The 2005-2006 car uses a different brake package with vented rear rotors, and makers catalog separate rotor part numbers for the 2004 car. Fitting the later rotors means converting to the later brake hardware.

Do I need to replace the front pads when I do the rears?

No. Pads are replaced per axle, and fronts and rears wear at different rates. Just avoid mixing very different compounds front to rear on a car you drive hard, or the brake balance can feel off.

Sources

1. Hawk Performance - HPS 5.0 - Ferro-Carbon compound, 100-750 F operating range, ABS-friendly design, iron rotors only
2. Hawk Performance - Street compounds - HPS, HPS 5.0 and Performance Ceramic temperature ranges and character
3. Hawk Pads Direct - 2005 Pontiac GTO - HB573B rear and HB247 front pad listings for the 2005 GTO
4. Hawk Pads Direct - 2006 Pontiac GTO - HB573B rear and HB247 front pad listings for the 2006 GTO
5. ViVA Performance - Hawk HB573B.615 - 2004-2006 GTO rear fitment, sold as a set of four
6. MartiniWorks - EBC rotors for 2005-2006 GTO 6.0 - 2005-2006 GTO 6.0 cataloged with vented rear rotors
7. Hawk Performance - HB247B.575 - Hawk's own HB247 fitment list (Corvette and XLR), which is why front fitment should be verified