Several things can cause brakes to squeak. One reason could be moisture on the brake pads when they contact the disc (also known as the brake rotor). The brake pad material can also squeak as the pads wear down through normal wear. But perhaps the most common culprit is the brake pad wear indicator. This indicator is a piece of metal designed to make the noise of metal-to-metal contact when your brake pads are worn down past a certain point. In that case, your brakes are sending you a clear signal: it’s time to replace the brake pads and have the brake rotor(s) resurfaced or replaced.

Checking the brakes is just one way to keep your car operating safely. It’ll also help you get the most for your car when you go to trade it in or sell it to a private party. For more ways maximize your car’s value, see How to Maintain the Value of Your Car.

Brakes generally refer to the entire braking system. Brakes include brake pads, calipers, rotors and, for older vehicles, brake drums. Brakes work together with the brake lines, which supply hydraulic pressure from the brake master cylinder under the hood. Brake pads are specifically the part of the brakes that apply pressure to the rotors or brake discs, “squeezing” the vehicle to a stop.

Depending on the vehicle you drive, there can be a pretty big difference in pricing. The average brake pad replacement costs around $150 per axle, but these costs can rise to around $300 per axle depending on your vehicle’s brake pad materials. The least expensive brake pads use organic material. More expensive composite brake pads incorporate metal, which gives them greater resistance to heat and less brake fade under heavy application.

The good news is that KBB.com shows you the Fair Repair Range for all types of brake repairs for your vehicle. It’s based on actual repair orders for actual cars in your actual area. And with almost a century providing trusted values and pricing, Kelley Blue Book is the best resource to have in your corner.

An average life span for brake pads should be around 40,000 miles. But there are several reasons why that life may be shorter or longer. If you often hammer on the brakes to stop suddenly or if you tow or haul a lot, your brake pads may wear out sooner. On the other hand, if you drive conservatively, slowly approaching a stoplight and applying gentle but steady pressure, chances are you may exceed that 40,000-mile mark. Either way, it makes good sense to care for your car well. For more on this, see Top 10 Car Care Tips.

Expect a brake job of replacing brake pads and rotors to cost $250-$400 per axle on average. If you drive a heavy-duty pickup truck and haul or tow a lot, your costs may go up quite a built. And going even further, if you drive a performance vehicle with specialized carbon-ceramic rotors and high-performance brake pads, the costs are high. For example, brake pad and rotor replacement for a carbon-ceramic rotor-equipped Mercedes-AMG vehicle could cost more than $15,000.