How much is an oil change for a 2020 Mercedes GLC 300?

The five core points of brake system maintenance include: First, regularly check the wear of brake pads and discs. It is recommended to inspect them every 5,000 kilometers. When the thickness of the brake pads approaches 5 mm or abnormal noises occur, they must be replaced. After replacement, a break-in period of 200 to 300 kilometers is required to achieve optimal braking performance. Second, brake fluid should be replaced every 20,000 to 40,000 kilometers or every 2 to 3 years. In humid areas, the interval should be shortened to 20,000 kilometers annually to maintain a stable boiling point and ensure moisture content does not exceed 3%. Third, maintain brake system cleanliness. Use specialized cleaners to remove oil and dust from brake discs, drums, and calipers to preserve heat dissipation efficiency. Fourth, routinely inspect brake lines and hoses. Immediate repairs are necessary if aging, leaks, or looseness are detected. Additionally, air must be bled from the lines to guarantee braking effectiveness. Finally, cultivate smooth driving habits by avoiding sudden stops and prolonged continuous braking. When descending mountain roads, utilize lower gears for supplemental braking. Note that emergency braking should be minimized during the first 1,000 kilometers of a new vehicle's break-in period. Any brake pulling or pedal abnormalities require prompt servicing to maintain system synchronization.

Repair of ABS brake system faults requires targeted measures based on specific causes. Common issues include dirty or damaged wheel speed sensors, abnormal signal wheels, circuit breaks or loose plug connections, and control unit malfunctions. First, diagnostic equipment should be used to read fault codes. If the sensor is dirty, it needs to be cleaned or the gap adjusted (the standard value is usually 0.3-1.0mm); if the sensor is damaged, it needs to be replaced, costing approximately 300-800 Malaysian Ringgit. For circuit problems, wire connections and fuses should be checked. If the ABS control unit is damaged, the repair cost may reach 2000-4000 Malaysian Ringgit. Additionally, the brake fluid level should be checked (if it is below the MIN mark, DOT4-compliant brake fluid needs to be added) and the power supply voltage (if it is below 10.5V, the system will shut down). If the hydraulic valve body has poor grounding, the contact surface should be cleaned and re-secured. Notably, using non-OEM specification tires or incorrect tire pressure can also cause speed signal deviation, triggering the ABS warning light. It is recommended to regularly inspect the brake system condition and avoid aggressive driving. If the warning light persists, professional repair services should be promptly contacted for diagnosis. While ABS failure doesn't affect basic braking functionality, it increases the risk of wheel lock-up on slippery surfaces.

The most common cause of brake system failure is issues with brake fluid, including insufficient fluid level, deterioration, or air trapped in the lines, which leads to inadequate hydraulic pressure and reduced braking efficiency. The second most common cause is excessive wear of brake pads or warping of brake rotors, which directly affects friction performance. Additionally, piston wear in the master cylinder or wheel cylinders, fluid leaks caused by seal failure, and vacuum booster pump malfunctions can also significantly impair braking force. Notably, long-term lack of maintenance resulting in contamination buildup in the master cylinder or brake lines can obstruct fluid flow. Overloading causes the brake system to operate beyond capacity, accelerating brake overheating and failure. It is recommended to regularly inspect brake fluid condition (replace every 2 years or 40,000 kilometers), measure brake pad thickness (replace if below 3 millimeters), and monitor abnormal symptoms such as spongy brake pedal or increased pedal travel, as these often indicate early-stage malfunctions. In case of sudden brake failure while driving, remain calm, immediately activate hazard warning lights, downshift to utilize engine braking for deceleration, and progressively apply the parking brake to assist stopping, avoiding abrupt pulls that could cause wheel lock-up.

To determine whether the brake caliper is stuck, a comprehensive observation of multiple symptoms is required, including abnormal caliper retraction after braking, increased vehicle driving resistance, and abnormal brake system feedback. When the brake pedal is released, if there is still a noticeable drag on the wheels or abnormally increased resistance when pushing the vehicle, it may be caused by corroded caliper pistons or deteriorated seals preventing proper retraction. If the steering wheel pulls to one side during braking while driving, it typically indicates uneven braking force between the left and right calipers, requiring inspection of the wheel cylinder pistons for seizure. Irregular wear or severe vibration of the brake disc suggests incomplete release of the brake pads by the caliper. Additionally, sluggish pedal return accompanied by persistent braking force often indicates blockage in the caliper's hydraulic circuit or contaminated brake fluid. Long-unreplaced brake fluid tends to absorb moisture, accelerating internal corrosion of wheel cylinders. It is recommended to replace DOT4-compliant brake fluid every 2 years or 40,000 kilometers. If these symptoms are observed, promptly inspect the lubrication condition of caliper guide pins, piston seals, and brake pad retraction springs. When necessary, replace the repair kit or entire wheel cylinder to prevent increased fuel consumption or brake overheating failure due to dragging brakes. During routine maintenance, regularly clean calipers and inspect dust boot integrity. Particular attention should be paid to potential water ingress and corrosion of guide pins after rainy seasons.

The "12/32" on brake pads usually indicates their thickness specification, where "12" represents the initial thickness of a new brake pad (approximately 12 millimeters), while "32" may be an internal manufacturer code or a specific series number and is not an industry-wide standard. Brake pad thickness directly affects braking performance. The thickness of new pads generally ranges from 10 to 15 millimeters, and they must be replaced when worn down to 3 to 5 millimeters to avoid brake failure or damage to the brake disc. When choosing brake pads, priority should be given to materials (such as ceramic or semi-metallic) and friction coefficient grades (e.g., grade F is suitable for daily driving), while ensuring the product has certifications like ECE R90. It is recommended to regularly check the thickness and wear uniformity, and replace them in pairs to ensure braking balance. After replacement, a break-in period of 200 to 300 kilometers is required to optimize performance.