Ferrari’s Secret SF25 Brake Pad Tests: What Lewis Hamilton’s Request Reveals About the Future of F1

Since the Canadian Grand Prix, Ferrari has been quietly conducting secret tests on their SF25 Formula 1 car—tests that only recently came to light. These tests center around a seemingly simple but critically important component: the brake pads. But this is not just about brakes; it sheds light on a deeper strategic move, influenced by none other than Lewis Hamilton, and hints at how Ferrari may be shaping their car for 2026’s looming technical revolution.

The Origin of the Secret Test

The story begins during preseason testing when Lewis Hamilton, freshly transitioned from Mercedes to Ferrari, noticed a significant difference in the braking feel between the Ferrari SF23 and the Mercedes cars he had mastered over the years. Hamilton, known for his precision and finesse when braking, found the Ferrari brake system notably rougher and less refined.

His concerns primarily involved the initial bite of the brake pads—the moment a driver first applies the brakes. Ferrari’s existing brake pads delivered a less sharp initial bite compared to Mercedes’ system, resulting in a different feedback and feel under braking. This difference became even more pronounced when combined with the engine braking characteristics of Ferrari’s power unit (PU), which differs significantly from Mercedes’ setup.

Hamilton’s Request and Ferrari’s Response

Driven by his desire for better braking feel, Hamilton requested a change: Ferrari needed to develop brake pads that offered a sharper, more aggressive initial bite. The goal was clear—make braking feel more intuitive, provide clearer feedback, and ultimately help Hamilton extract more performance from the car.

In a surprising twist, Ferrari did not test this new brake pad first on Hamilton’s car. Instead, it was Charles Leclerc who was given the upgraded component during the Canadian Grand Prix. This decision has raised eyebrows, as the driver who initiated the request was not the first to benefit from it.

The Impact on Performance and Incidents

This new brake pad brought a more immediate and sharper bite to the SF25’s braking system. Drivers reported getting more feedback from the initial input on the brake pedal, which theoretically allows for more precise braking and potentially better deceleration.

However, the introduction of this component came with challenges. For example, Leclerc’s crash during FP1 at the Canadian GP has been linked to the differing feel of the brake pad. Similarly, Hamilton’s struggles with rear locking in qualifying at the Belgian Grand Prix were reportedly influenced by the brake pad’s characteristics combined with Ferrari’s engine braking.

Brake Balance and Driving Style Adaptations

The sharper initial bite meant drivers needed to adjust the brake balance of the SF25, shifting it more towards the front. This shift is significant because brake balance affects how the car behaves under deceleration and corner entry.

Interestingly, Hamilton uses the brake system more “closed off” than Leclerc, meaning he modulates the brakes differently. This driving style difference explains why Hamilton receives fewer “lift and coast” messages from his race engineer compared to Leclerc. “Lift and coast” is a technique used to save fuel by gently lifting off the throttle and coasting into braking zones—drivers’ styles affect how and when they use this.

Engine Braking: A Crucial Factor

Another major factor in braking feel is engine braking—the deceleration effect caused when the driver lifts off the accelerator, influenced by the power unit’s design.

Mercedes engines are known for delivering relatively less engine braking, resulting in a more stable rear end under braking. Ferrari’s power unit, in contrast, provides stronger engine braking, which tends to rotate the rear of the car more. This requires a different driving approach to maintain stability, something Hamilton is still adapting to.

Leclerc, having spent several years with Ferrari, is naturally more comfortable with this characteristic. Hamilton, meanwhile, is adjusting to the different balance and behavior that Ferrari’s PU imposes on braking.

Why Ferrari’s Testing Matters for 2026

The secret brake pad tests are not just about improving the current season’s performance—they are a strategic move looking forward to the major technical regulation changes arriving in 2026.

Formula 1’s 2026 regulations will introduce substantial changes to power units, with a 50/50 split between electric and internal combustion components, and major modifications to hybrid systems. Ferrari, like all manufacturers, is under pressure to develop a power unit that’s competitive under the new rules.

The brake pad development and testing now help Ferrari gather valuable data about how different braking feels and engine braking characteristics affect driver performance. This information is critical to shaping the 2026 power unit and brake system designs. Since the power unit is not yet homologated, Ferrari can still make adjustments based on this feedback.

Hamilton’s Influence: Steering Ferrari’s Development?

It’s particularly interesting that Hamilton’s input initiated this development. It suggests that he may be encouraging Ferrari to move toward a braking and engine braking feel closer to what he experienced and thrived with at Mercedes.

If Ferrari can align their power unit’s engine braking and brake pad characteristics more with Hamilton’s preferences, it could ease his adaptation and unlock his full potential in the SF26.

What This Means for the Rest of 2025

For the remainder of the 2025 season, Ferrari’s aim is to refine these components and help both drivers adapt. With the new brake pads now on both cars, the team will collect data from every session and race, feeding this knowledge into the development of next year’s car.

Adjustments to brake balance, driving style accommodations, and managing engine braking will be ongoing tasks. The team’s ability to manage this will be crucial to their competitiveness.

Conclusion

Ferrari’s secret brake pad testing highlights the intricate interplay between driver preference, component design, and power unit characteristics in modern Formula 1. Hamilton’s influence has spurred a change that may have long-term ramifications for Ferrari’s car design philosophy.

As 2026 approaches, the lessons learned from these tests and the adaptations made this season will be invaluable. Ferrari is not just chasing performance improvements for today—they’re laying the groundwork for a power unit and braking system optimized for the future.

Fans and experts alike will be watching closely to see how these developments affect Ferrari’s performance in the remaining races and beyond. The coming season promises to be a fascinating one, shaped by subtle technical evolutions and the insights of one of F1’s greatest drivers.