Q: I have a 2009 Lincoln MKX. One of its right wheels has been squeaking badly for a long time.
I've taken it to a Ford dealer repair shop four times. The first time, they blew some dust from it and said it was all set. Not so. I took it back, but they couldn't find anything. I took it back again, and they greased it or something. But that still didn't help.
It sounds like it needs brake shoes, but of course, the shop doesn't do that anymore.
By the way, the wheel only squeaks when going backward.
After my earlier trips, I took it to a different Ford place, and they filed the pads and turned the rotors. They promised the problem would be solved. Yet the very next day, the wheel was back at it, albeit not as bad.
My loud wheel really draws some attention on the road. Can you help me?
-Bess F.
A: Bess, I agree with your prognosis. The front brake pads should be replaced with a premium-level product that promotes quiet operation.
In my opinion, the existing pads are acting up for one of the following reasons: They're glazed from high-temperature operation, they're of inferior quality, or they were engineered for endurance rather than quiet operation.
While Ford original equipment pads are good, there are aftermarket pads that exceed them in performance and are designed to operate quietly. I checked RockAuto.com and found 30 different front brake pads to choose from.
Perhaps your dealer will take another stab at the repair by renewing the pads with no labor charge. After all, they promised! They'll probably not be keen on installing aftermarket or customer-supplied parts, so you might need to go with their original equipment pads.
Another option is finding an independent shop that does a lot of brakes and going with their recommendation for a premium set of pads.
Rotor surface finish is really important. Even though your pads were just machined, it's possible that turning left them rough. Most good pads come with insulating shims, which help isolate the pad from the caliper and piston. On shim-free pads, an application of CRC Disc Brake Quiet (an orange, glue-like substance) is a good method to minimize noise.
Q: While recently replacing the front brake pads on one of our cars, a 2007 Nissan Altima S, I noticed an old oil leak on the passenger-side strut. It didn't look like a recent leak as oil was not continuing to drip and the top half of the strut, where the oil had leaked, was covered in dust. The car drives fine, and a bounce test performed on each side seemed to produce the same response. Should I replace the strut? If I do, should I replace the driver's side as well? Also, do you have any recommendations on a good, inexpensive aftermarket brand? And lastly, should I get the wheels aligned?
-Gary
A: It's hard to say how much fluid was actually lost from the previously leaking strut, and the bounce test doesn't really work on modern cars like it did years ago.
Most modern shocks and struts contain multiple valves, each regulating a certain type of motion. A bounce test, at most, will infer only that one type of valve seems to be working.
Symptoms of worn or defective shocks or struts include excessive body roll, acceleration squat, traction loss on washboard surfaces, ride harshness and braking nose dive.
If the struts have more than 50,000 miles on them, they're candidates for replacement. My personal favorite is KYB, although other brands are certainly competitive.
Checking wheel alignment is recommended as the strut is a suspension member and the replacement part you choose could differ slightly in dimensional layout. Think of it as insurance for good tire life.
ABOUT THE WRITER
Brad Bergholdt is an automotive technology instructor at Evergreen Valley College in San Jose, Calif. Readers may send him email at [email protected]; he cannot make personal replies.