Braking system

The entire process begins with applying pressure to the brake pedal: this action allows us to regulate the braking progressively, so that we can reduce driving speed, maintain a constant speed when travelling downhill, or stop the vehicle completely.
The force exerted on the pedal is transmitted to the brake pump piston to create friction, thereby ensuring:

• the closure of the calipers to press the pads onto the discs
• the expanding of the shoes to press them against the drums
  

For safety reasons, the braking system is split into two separate circuits, but action on the brake pedal is directed on to all four wheels.
Respecting ergonomic standards is essential to ensure brakes work safely and comfortably.

Nowadays, electronic systems are available to assist the driver in the case of emergency braking: if the driver presses the brake pedal quickly, the BAS (Brake Assist System) understands that this is an emergency situation and, via the ASR pump, instantly increases braking power, maintaining constant pressure on the system until the vehicle has completely stopped. The immediate result is a reduced braking distance, and the emergency braking is indicated on the outside of the vehicle, with the automatic activation of the direction indicators.

The brake pump slows us down too!

All vehicles fitted with hydraulic braking systems are equipped with a brake pump, technically known as the master cylinder, which converts the physical pressure applied to the brake pedal into hydraulic pressure. When the brake pedal is pressed, the brake servo amplifies the energy exerted, so that the force produced is around 100 times greater than that generated by the pressure we apply.

Brake pads and discs are the main elements of the braking system. An essential pair of components, tried and tested on every vehicle, for optimum response during both ordinary and emergency braking.
The technology used to construct the friction material is the true heart of the brake pad. During the design phase, the brake pad components are designed and optimised to ensure maximum performance.
A single material, used for multiple applications, cannot guarantee the same quality standards as the complex mixtures developed during the original brake pad design phase: the mixture of braking materials must have a friction coefficient which is suitable for the specific type of braking system and must ensure efficient braking, guaranteeing the same results at every operating temperature.
To create a product which meets all applicable safety requirements, it is crucial that the following elements, which make up the mixture, are combined in a balanced manner: resins, rubber, talc, metals, carbon fibres, glass and ceramics.
The number of ingredients in an original mix, linked together with thermosetting resins, may be more than twenty.

Brakes Pads

The brake pads (one pair per disc) are part of a calliper system which, during braking, exerts pressure on the disc, creating the friction required to slow down or stop the vehicle.

Brake pads and discs are the main elements of the braking system. An essential pair of components tried and tested on every vehicle, for optimum response during both ordinary and emergency braking.

Brake Discs

Original brake discs are comprehensively checked and balanced with maximum precision, ensuring the complete absence of troublesome vibrations, decreasing braking distances and guaranteeing long-lasting safety and reliability. Each individual component is marked with a code to ensure the total traceability of the product.

A drum brake is made up of a rotating cylinder integral to the braking system (known as the "drum") and one or more blocks made from friction material which exert force on the cylinder: these are known as shoes. The brake holder plate has a cylinder which, when under pressure, presses the shoes against the drums.

Contrary to what you might think, drum brakes achieve deceleration levels which are fairly high compared to those of a calliper and disc system. Drum brakes, once de-energised, do not generate friction, which may occur in disc systems. This is because brake pumps do not have the capacity to recall the pistons from the calliper to their housing, therefore resistance occurs, although minimal and for a very short period of time, caused by the pads which remain pressed on the disc.

The flexible brake pipes transmit the pressure applied to the brake pedal, distributing it into the system via the brake fluid in the form of hydraulic pressure, required to slow down or stop the vehicle. The pipes connect the brake pump with the calipers or the drums, in order to transmit the hydraulic pressure to the pads or shoes. These are subjected to strong dynamic stresses, but even in the most extreme conditions, they ensure the correct transmission of the hydraulic pressure, thanks to different types of resistance:

• mechanical (flexing, stretching and resistance to pressure)
• chemical (oil, fuel and other environmental agents)
• thermal
  

The brake pipes influence your car's braking performance: a brake pipe which is too old may require a braking distance which is dangerously higher than that required to stop your vehicle safely and avoid a collision. For this reason, it is a good habit to get into to have your brake pipes checked once every 2 years.

To protect the braking system components, it is especially important to use the correct brake fluid, a crucial element in the correct operation of the braking system and which allows the braking assembly itself to be activated.
 
To ensure maximum vehicle safety and maintain efficient braking, it is important not to underestimate some of the important parameters of this fluid, which must remain constant over time.

A brake fluid must offer a range of characteristics, all of which are crucial to driver and vehicle safety:

• Boil resistant to prevent vapour bubbles from forming in the system ("vapour lock")
• Viscosity index, which must be suitable for ensuring the correct operation of the system even at the lowest temperatures (−40°)
• Hygroscopicity: the brake fluid must have the capacity to absorb the humidity which penetrates and condenses in the braking circuit
  

The brake fluid must have sufficient lubricating power to ensure the smooth functioning of the mechanical components without causing wear or corrosion of the metal parts leading to the formation of rust in the system.

Petronas Tutela Brake Fluid TOP4 is a brake fluid with a synthetic base for hydraulic disc and drum braking systems and servo-controls in cars, commercial vehicles, industrial vehicles, scooters and motorcycles (where an NHTSA 116 DOT 4 control fluid is required), with specific characteristics:

• A high boiling point (+270 °C)
• High hygroscopic power
• A low pour point for use at low ambient temperatures (down to −40 °C)
• Excellent anti-corrosion, anti-rust and anti-oxidation properties to protect the braking system's metal components
• Complete compatibility with rubber parts and trims to avoid swelling or weakening of rubber or plastic sleeves and their relative seals
• High chemical stability to ensure that it does not alter, even under the harshest thermal stresses.
  

Petronas Tutela Brake Fluid TOP4 holds the following international technical specifications: DOT4, FIAT 9.55597, CONTRACTUAL TECHNICAL REF.No.F001.A93.

Fiat Group servicing plans set out the replacement of the brake fluid once every 2 years.

Petronas Tutela Brake Fluid TOP4 and all other PETRONAS brake fluids have been designed and manufactured to meet the strictest safety standards, and exceed the minimum permissible thresholds set out by international legislation for a range of parameters.

Petronas products is demonstrated by their C.T.R. (Contractual Technical Reference); a type approval, unique to each product, which is issued on the basis of tests carried out directly by Fiat Group Automobiles. The Contractual Technical Reference certifies the exclusive type approval of each one of our products on behalf of the Fiat Group.

To ensure you choose the products recommended for your vehicle, simply follow the guidelines in your owner handbook. Respecting the servicing plans and using the correct lubricants, fluids and original spare parts will extend the reliability and safety of your vehicle over time.