Do You Need to Replace Brake Discs When Changing Brake Pads?
3 Answers
Replacing brake discs is not mandatory when changing brake pads; typically, brake discs are replaced every second brake pad change. Brake discs should be promptly replaced when the combined groove depth on both sides exceeds 3 millimeters or when the edges become sharp. It's essential to develop a habit of regular inspections and timely maintenance. The replacement cycle for brake pads is not only directly related to their lifespan but also depends on the vehicle's driving conditions and the driver's habits. New brake pads are approximately 1.5 centimeters thick and should be replaced when worn down to about one-third of their original thickness, or 5 millimeters. When replacing brake pads, both sides of the same axle must be changed simultaneously to ensure balanced braking performance.
I've been driving for over a decade, and every time I change the brake pads, I make sure to inspect the condition of the brake discs. However, I don't necessarily replace the discs every time. If the disc surface remains smooth and the thickness is within the normal range (generally more than 22mm), there's no need to replace them—saving money is always good. Since I drive smoothly and avoid sudden braking, my brake discs tend to last longer. But if there are deep grooves, cracks, or excessive wear (making the disc too thin), they must be replaced immediately. Otherwise, braking performance suffers, especially at high speeds, which can be extremely dangerous. Always have the mechanic use a thickness gauge to measure the discs—safety should always come first. Don't cut corners to save a few bucks and end up paying a much bigger price.
As a driver, I believe that changing brake pads doesn't necessarily require simultaneous replacement of brake rotors—it mainly depends on the rotor's wear condition. If it's still thick with no severe scratches, it can continue to be used. However, if it's excessively worn or shows abnormalities, both should be replaced to ensure braking safety. I've noticed during maintenance that driving habits play a significant role: sudden braking and overloading accelerate wear, so I try to anticipate road conditions and drive smoothly. When replacing pads, don't skip checking the rotor's condition. I always ask the technician to measure its thickness with professional tools to avoid potential risks, ensuring better vehicle maintenance and longer lifespan.
