Brake rotors are an often overlooked component essential to safely and reliably stopping your car. And just like brake pads, they wear down over time. DIYers and thrifty car owners like to replace their own to avoid the high labor cost. But sourcing the correct part can be difficult.
There are many kinds of rotors out there, so choosing the right brand and model will come down to your car, driving habits and budget. The best brake rotors for most commuters and daily drivers are Bosch QuietCast Premium Disc Brake Rotors.
Brake rotors are the metal discs inside your wheel well. They're attached to the axle and are a part of your tire's mounting hub. Each disc is composed of sandwiched vanes between two plates. These vanes form gaps between the metal plates that vent heat. These days, most cars use brake discs on all four wheels, though some older brake systems might mix in a set of drum brakes in the front or back.
Brake-disc rotors serve as a stopping surface for your calipers and pads. When you depress the brake pedal, the caliper clamps down on the rotor. The friction between your brake pads and your rotors slows your forward momentum, bringing your car to a stop. Rotors serve a second function in this process, helping dissipate the immense amounts of generated heat so that your pads don't glaze over and lose their bite.
Throughout your day-to-day driving, your rotors' surfaces wear down. This degrades your brake system's stopping power, which reduces the overall safety of your vehicle. It is generally recommended that you replace or resurface your rotors every 70,000 miles (or every other brake job). You should only resurface once, and a resurface won't last nearly as long as fresh rotors.
Some signs that its time to replace your rotors include: shuddering or vibrations when braking, warping or etched grooves in the surface of the rotor and squeaking, grinding or squealing sounds when braking.
Brake rotors are sized to fit your car's specific year and model. Most OE rotors and performance kits are manufactured for a range of cars, SUVs and trucks. When reviewing your options, be sure to verify that the brand's brake-rotor line has a kit for your vehicle.
Rotors also play a crucial role in maximizing your car's performance. Amateur and professional motor enthusiasts alike will replace the stock rotors with high-performing, aftermarket rotors to improve the stopping power of their cars. These special kits dissipate as much heat as possible, so your brakes don't fade during hot laps at the track or autocross course.
Original-equipment-manufacturer rotors are almost always iron. It's cheap, good at dissipating heat and lasts long.
Performance rotors can be made from a few materials. Steel offers a lightweight alternative for the track but wears much quicker. High carbon mixes carbon with iron for a long-lasting, high-heat tolerant, but expensive option. And ceramic rotors have some of the highest heat capacities and are often found on exotic cars.
Unless you're shopping for a motorcycle, you won't want pure aluminum as this material is too light for large vehicles and is prone to excessive wear.
When choosing your vehicle's rotors, make sure to verify the size for your make and model. There are two primary measurements of concern. These are the diameter and the thickness of the rotor. Too large a rotor can obstruct your suspension, impede your brakes and often won't even fit inside your wheel or caliper. You also want to make sure the rotor's bolt pattern matches your hub and wheel. When in doubt, compare the part number of the aftermarket rotor to your OEM rotor's part number.
Rotors are often sold in sets of two for your front and rear wheels. OE and blank rotors usually cost $100-$200 for a set of four. Performance rotors can be pricier and often come with pads. These cost anywhere from $200-$500 for a full set.
A. Drilled and slotted rotors have become a popular performance modification for cars. But they're a poor choice for daily drivers and track cars. Not only do the holes and slots increase the likelihood of your rotors cracking, but they also reduce the surface patch your pads have to grab onto and stop your car effectively.
A. All rotors eventually wear down to the point of needing replacement. But you can shorten their lifespan with your driving style. Riding or slamming the brakes creates significant friction and strain on your rotors. Worn pads can also grind grooves into the rotors and warp them.
What you need to know: Bosch is known for making reliable aftermarket OEM replacements, and their QuietCast rotors are no exception.
What you'll love: Best for daily drivers and commuter vehicles, QuietCast rotors are designed to mimic your car manufacturer's original rotor design. They're not only quiet on the road but also improve on OEM stopping power. And because they're cast from steel, they're adept at dissipating heat, while their aluminum-zinc coating helps prevent rust.
What you should consider: This specific model is for certain Toyotas, so be sure to source the right QuietCast model for your vehicle. Some users report vibrations after 10,000 miles.
Where to buy: Sold by Amazon
What you need to know: This brake-pad and rotor kit from a popular aftermarket brand upgrades performance while retaining the OEM configuration.
What you'll love: If you're doing your brakes yourself, this is the kit to get. You get one set of iron rotors and corresponding, Z17 Power Stop Evolution ceramic brake pads. This way, you can swap everything out at once. They're great for daily drivers and amateur track enthusiasts.
What you should consider: These are specifically for Hondas. Sold as a pair, you need to buy two sets. Some users complain that the brake pads wear too quickly.
Where to buy: Sold by Amazon
What you need to know: Truck and SUV owners swear by AC Delco as a premium OEM replacement for heavy-duty rotors.
What you'll love: AC Delco is a General Motors-owned factory parts manufacturer, so you know you're getting quality. Their gold series rotors are made from solid iron for a combination of excellent stopping power and durability. They're designed to minimize pulsation and noise, which are common issues with larger vehicles.
What you should consider: This single front rotor is for GM trucks and SUVs specifically. You'll need to order two fronts and then separate rear rotors. AC Delco also manufactures parts for non-GM vehicles, so be sure to verify fitment.
Where to buy: Sold by Amazon
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Karl Daum writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.