Q My wife's 2001 Pontiac Grand Am GT with 37,000 miles on it has a squeaky caliper on the left front corner. You can hear it at slow braking speeds, as well as when the car is stopped and in park when you pump the brake pedal. I pulled the caliper and can find nothing wrong. I don't perceive this as a safety issue, but rather a perpetual annoyance. Any ideas and should I be worried about safety?
A I was about to suggest lightly lubricating the slider pins with high temperature silicone grease but found an interesting service bulletin in my Alldata database. Bulletin 04-05-23-004, dated September 2004, identifies a "creak" from the caliper that is heard during low-speed braking and can be duplicated with the vehicle standing still. The noise may be "caused by caliper piston-to-seal interface issue" during brake application. The bulletin suggests injecting "Kluber Fluid" between the caliper piston and dust boot to lubricate the piston-seal interface. The product is German and available at GM dealers.
Q I have 2004 Chrysler Sebring convertible, and the air-bag light comes on intermittently. It can come on when I first start the car or when I am driving, and then go off for a few minutes or days before coming back on. The Chrysler service people have not been able to determine the cause. Incidentally, it happens whether I have a passenger with me or not. Do you have any suggestions?
A The air-bag control module monitors the readiness of the air-bag system, tests the system at every startup and illuminates the air-bag warning light should a fault develop. It also stores the fault code in hard memory. A scan tool should identify the cause of the intermittent air-bag light. An intermittent connection through the clock spring in the steering-wheel hub may be the primary suspect.
Q What is the best way to decrease tire/road noise in a new Buick Lucerne without replacing the Michelin MXV4 tires? It seems to be coming from the trunk area.
A Ask the dealer to swap the wheels and tires on your Buick for a set from another new Buick -- or test drive an identical Buick off his lot. If the replacement set is quiet, ask the dealer if you can keep them! If not, have the dealer check for a problem with one of the rear hub/wheel bearing assemblies. Also, have them check for unusual wear or a defect with your tires, and rotate them on your vehicle. Increasing tire pressures to perhaps 35 pounds per square inch may help.
Motoring note I received this e-mail from Sondrea Rein in response to last week's item about tire-wheel vibration on the '99 Saab:
"Just read your column this morning about the vibration in steering at high speeds. My new Rogue with less than 3,000 miles on it started vibrating at 50 mph. Took it in to dealership immediately and was shown the fresh tar build-up in the front tires. I was shocked that this could affect the driving that much. Cleaned most of it out and the car drives fine now. I've never been aware of this before and have been driving for over 40 years."
