2004-2012 Aston Martin DB9 Brake Upgrade Options

By Core Brake Parts Tech Team — Circleville, OH warehouse

On a 2004-2012 Aston Martin DB9 with the standard steel brake system, the real upgrade is the friction material, not a bigger caliper. The factory hardware is already a four-piston Brembo caliper at each corner clamping a 355 mm ventilated front disc and a 330 mm ventilated rear disc, so a better pad compound changes how the car stops far more cheaply than any caliper swap. The decision that matters is which compound suits your driving, and whether your car left the factory with steel discs or the carbon ceramic option.

What the factory DB9 brake system actually is

The Aston Martin DB9 workshop manual describes both the front and the rear brake as a one-piece caliper body containing four pistons, attached to the vertical link with two bolts. The two pairs of pistons act directly on the pads, one pad each side of the disc. All four discs are ventilated steel with surface grooves that clear water off the face, and each disc is held to the hub by two small screws rather than by the wheel alone.

Brembo's own catalogue data for the DB9 6.0 V12 fills in the dimensions: the front disc is 355 mm in diameter and 32 mm thick, the rear is 330 mm in diameter and 28 mm thick, both ventilated, both on a five-hole hub. The rear corner also carries a second, small handbrake caliper mounted separately to the vertical link, which is why a rear brake job on this car involves more than a service caliper and two pads.

Steel or carbon ceramic: check before you buy anything

Aston Martin offered a carbon ceramic matrix system on the DB9 line, and its own model page lists that setup as ventilated carbon ceramic discs of 398 mm at the front with six-piston monobloc calipers and 360 mm at the rear with four-piston monobloc calipers. Aston describes those brakes as giving better response with longer life and improved performance with virtually no fade.

Those are different diameters to the 355 mm and 330 mm steel discs, which means the caliper, the caliper mounting and the pad shape are all different. A pad or disc listed for the steel car will not fit a carbon ceramic car. Before ordering, look through the wheel: measure the disc diameter, or check the disc face. A ceramic disc has a distinctly different grey, grainy friction surface and no rust bloom on the edges after the car sits. If the car has ceramics, nothing in this guide about pad compounds applies to it, and pad choice is limited to what the ceramic system is approved for.

The pad is where the upgrade lives

With a four-piston fixed caliper and a 355 mm ventilated disc already fitted, the DB9 is not short of clamping force or thermal mass for road use. What owners usually want to change is one of three things: dust on the wheels, bite when the pads are cold, or fade resistance on a fast road or a track day. Those pull in different directions, and no single compound wins all three.

EBC publishes its own descriptions of the two compounds most DB9 owners choose between. Redstuff is a copper-free organic pad enhanced with ceramic granule, non-metallic with zero steel fibres, which EBC credits with extremely minimal brake dust that is very easily removed with a simple sponge wash. EBC quotes a 10 to 15 percent increase in braking performance over standard and aims the compound at faster street driving for prestigious and sports vehicles, specifically calling out cars with intricate wheel designs that are a chore to clean.

Yellowstuff is the harder-working option. EBC quotes a 15 percent increase in braking performance over the original equipment part, describes the compound as copper-free and R90 approved, and positions it for faster street driving on sports vehicles along with occasional track day use. For dedicated track work EBC sends you elsewhere: its bedding guidance states that Yellowstuff is not recommended for track because of the long bed-in it now requires, and its Bluestuff and racing compounds are the intended answer.

Choosing between the two compounds

For a DB9 used as a fast road car that lives outdoors and wears polished wheels, Redstuff is the honest answer: Redstuff front pads DP31908C with Redstuff ceramic rear pads DP31909C. For a car that gets driven hard on mountain roads or sees the occasional track day, Yellowstuff front pads DP41908R with Yellowstuff rear pads DP41909R are the compound EBC builds for that use. Mixing compounds front to rear is not worth doing; brake balance on this car was set with matched friction at both ends.

Discs, wear limits and what to replace at the same time

The manual gives hard numbers, and they decide whether your existing discs can carry a new set of pads. A front disc starts life at 32 mm thick and must be replaced at 30 mm. A rear disc starts at 28.0 mm and must be replaced at 26.0 mm. That is only 2 mm of wear allowed per disc, total, across both faces. Disc runout must stay under 70 microns measured 2 mm in from the outer edge, which is the specification to check if the car has a pulsing pedal rather than a low one.

Pads have their own limits. A new front pad measures 9.4 mm, and the minimum lining thickness front or rear is 2.5 mm. The manual adds a practical instruction that is worth following: replace the pad if less than one third of the friction material remains, the car is used regularly, and there is a long period before the next service.

• Pad wear sensor. The manual is explicit that when you install new pads you must install a new brake pad wear sensor. Do not reuse the old one.
• Caliper bolts. The two bolts holding each caliper to the vertical link are removed and discarded, and new bolts must be fitted. The manual warns that reused bolts can break and cause brake failure.
• Brake fluid. The specified fluid is Castrol Super Response DOT 4, explicitly not a silicone-based fluid, with a system quantity of 2.5 litres.
• Shims. Left and right pad shims must go back in the same positions they came out of, so record them at removal.

If the discs are near the wear limit, do the discs and pads together rather than putting fresh friction material against a worn, hard-glazed face. Our brake pad range and brake disc range cover both sides of that job.

Torque values and the factory bedding procedure

The manual's published torque figures for this system are: caliper to vertical link 20 Nm, then a further 66 to 70 degrees, using new bolts; handbrake caliper to vertical link 15 Nm then a further 90 to 94 degrees; brake disc screws 10.5 Nm; brake hose unions 22 Nm; brake hose bracket to body 9 Nm. The hose has an alignment line that must sit straight after the union is torqued, because a twisted hose can fail.

Aston Martin also publishes a specific bed-in routine, and it matters because the manual warns that skipping it can leave reduced brake performance, judder or squeal. Start with cold brakes, below 80 degrees C. Slow the car three times from 100 km/h to 32 km/h at 0.3g, then drive 3 km to cool. Slow it three times from 100 km/h to 32 km/h at 0.5g, then drive 4 km to cool. Finally, use the ABS and stop from 100 km/h to rest three times, then drive 8 km to cool. The whole procedure takes roughly 17 minutes in a controlled environment.

EBC layers its own guidance on top. Its pads carry a brake-in surface coating that scrubs the disc and speeds up seating, and on the street it says bedding completes over the first 100 to 150 miles of normal use. EBC also warns that if you drive hard after seating, and certainly not before 300 miles, the pads may smell or smoke as surface volatiles burn off when the discs first reach 400 to 500 degrees C. That is expected, not a fault.

Frequently Asked Questions

Can I fit bigger brakes to a 2004-2012 DB9?

Physically, larger systems exist, but the factory car already runs a 355 mm front disc inside a four-piston Brembo caliper. On a road car the gain from more disc diameter is small next to the gain from the right pad compound and healthy fluid, and a caliper change brings mounting, hose, wheel clearance and brake balance work with it. Change the friction material first.

How do I know if my DB9 has carbon ceramic brakes?

Measure or compare the disc diameter. Aston Martin lists the carbon ceramic setup as 398 mm front and 360 mm rear with six-piston front monobloc calipers, against 355 mm and 330 mm for the steel system. A ceramic disc also has a grainy grey friction face and does not develop surface rust when the car sits. The two systems do not share pads or calipers.

Which compound keeps the wheels cleanest?

Redstuff. EBC attaches its dust claim to that compound specifically, describing extremely minimal dust that comes off with a simple sponge wash, and it names intricate wheel designs as the reason. No equivalent low dust claim is made for Yellowstuff, which is sold on braking effect and occasional track day capability instead.

Do I need new discs every time I change DB9 pads?

Not automatically. Measure them. The front disc is scrap at 30 mm and the rear at 26.0 mm, and runout over 70 microns means the disc is finished regardless of thickness. If the disc is within a few tenths of the limit, replace it with the pads rather than half way through the new pads' life.

How long before new pads feel right?

Follow the factory bed-in first, then give the compound time. EBC says its brake-in coating gives a strong brake effect for the first 100 miles while the pad seats, and that street bedding completes over roughly the first 100 to 150 miles of normal driving. A slightly soft first week is normal; a pedal that stays long is a hydraulic problem, not a bedding problem.

What else should I check while the wheels are off?

Look at the flexible hoses for bulging or cracking, check the pad wear sensor wiring, and confirm the handbrake caliper at each rear corner moves freely, since it is a separate unit from the service caliper on this car. Also check the fluid: the system holds 2.5 litres of DOT 4, and old fluid absorbs moisture and drops the boiling point that a high-friction pad depends on.

Sources

1. Aston Martin DB9 Workshop Manual, Brake Systems section 06.00 - disc thickness and wear limits, runout, pad thickness, fluid specification, torque figures and the factory bed-in procedure
2. Brembo parts catalogue, Aston Martin DB9 6.0 V12 - front and rear disc diameter, thickness and ventilated construction
3. Aston Martin, DB9 model information - carbon ceramic disc diameters and caliper piston counts
4. EBC Brakes, product focus on Yellowstuff pads - 15 percent braking gain, copper-free and R90 approval, intended fast street and occasional track day use
5. EBC Brakes, product focus on Redstuff pads - compound description, zero steel fibres, dust behaviour and the 10 to 15 percent braking gain
6. EBC Brakes, bedding-in procedures - brake-in coating, street bedding distance, surface volatiles and track compound guidance