Automotive Q&A: Check out those squealing brakes

Q: The brakes on my car began to squeal this week and a friend said it means it's time for a brake job. I've heard ads on the radio about a "lifetime" brake job and wonder if this could be as good as it sounds. What's your take on such a deal? Also, does the squeaking mean I need brakes for sure?

A: Oh boy, this ought to be good for some lively responses! I have a hard time with a lifetime brake warranty as brake pads and shoes will wear out, and somehow the entity providing the free replacement brakes needs to recover costs. Here's my view on brakes:

Brake pads and shoes come in a multitude of composition formulas. Some are long lasting, prone to noise, stop adequately and are tough on the brake rotors — perhaps the lifetime version? Others may wear more quickly, operate quietly, provide superior performance, are easy on the rotors and spew more dust. In either case, pads and shoes wear out in maybe 30,000 to 70,000 miles.

Other brake components that may require attention are the brake rotors and drums, calipers, master cylinder, hoses, brake shoe hardware and antilock brake system components.

Rotors and drums can become scored, worn, warped or cracked. With gentle use, rotors and drums may last through two, possibly three pad or shoe replacements before needing service. Under demanding use, these parts may require machining (to restore a smooth, consistent friction surface) or replacement should the part become excessively warped, cracked or too thin.

Brake calipers clamp the pads to the rotors and contain a hydraulic piston and seal. With periodic fluid flushing/renewal, calipers and drum-brake wheel cylinders can last the life of the vehicle.

Same goes for the master cylinder, the pressure-creating device connected to your brake pedal. ABS components are similarly reliable, as long as the brake fluid is periodically renewed. Brake hoses and brake hardware (springs, retainers, adjusters) and rubber brake hoses may require renewal perhaps every 10 years/100,000 miles.

Recommendations for renewal or service of the above parts can be a subjective call. As a GM dealership tech for many years, I renewed countless pads and shoes, machined or renewed brake rotors and drums when justified and occasionally recommended replacement of calipers, wheel cylinders and other parts.

Other facilities were much more aggressive suggesting service that exceeded our recommendations. "Loaded calipers" (replacement calipers containing new brake pads) are, in my opinion, a rarely needed and profitable upsell.

The bottom line is, you may encounter a tough time exercising your lifetime brake pad/shoe warranty, one day in the future, without being pressured for substantial additional and possibly elective repairs.

You'll hear: "We can't ... unless you ..." I'd prefer to do business with a shop that repairs cars rather than one who sells brakes. Try Googling "lifetime brakes," and make your own call.

Squealing (repetitive or constant while not braking) is likely the brake wear sensors hollering for attention. Squealing as the brakes are applied can also mean your brakes are worn out, or maybe they're simply glazed and rapidly vibrating. In either case, a brake inspection would be prudent.

Brad Bergholdt is an automotive technology instructor at Evergreen Valley College in San Jose. Readers may send him e-mail at under-the-hood@earthlink.net; he cannot make personal replies.