Michelin Pilot hx mxm4 oem (original equipment) tires at 40,000 miles have chunks of tread coming off both of the front tires (the form does not permit noting more than a single tire but it is both front tires) of a well-maintained, dealer maintained (under warranty and then under GM protection plan extended warranty) one-owner vehicle. Internet search shows this is widespread problem and that Michelin acknowledged a manufacturing defect in this tire line. Yet Michelin never recalled the tires and Michelin representative was unconcerned with the safety implications, only discussing warranty issues not the safety issue which was the basis of my call.

- Larchmont, NY, USA

2009 Cadillac Cts has serious vibration at highway speed, after several attempts to resolve, changing the left front and the right rear tire, the dealer claims the car operates as designed, I see other complaints on Consumer Affairs website of the exact same issue. I have asked the service manager of the dealer to ride with me in the car. He failed to do so, and didn't show up for two appointments at his dealership to drive the car. The vibration was present when I test drove the car the owner of the dealerships son told me the vibration existed in many cars because of the tires getting flat spots. He assured me it would go away in 200 miles or so. 10,000 miles later the vibration still present. Since the vibration is worst between 64 or 75 miles an hour, and causes the steering wheel to shank the potential for a serious accident exist anytime the cars are driven on the highway.

- Warrenton , VA, USA

Vibration in steering wheel, floor and seats. Also a thumping sound coming from tires during the first few miles of driving. At times the vibration is so bad you can see the steering wheel shimmy from side to side. The dealership replaced two of the oem Michelin tires which did not resolve the problem. Then they force road balanced the tires a couple of times, again did not resolve the problem. Dealership now stating they cannot duplicate the problem.

- North Port, FL, USA

2009 Cadillac, Cts sedan. Consumer states defective tire compressor the consumer discovered the vehicle did not come with a spare tire. The dealer informed the consumer Cadillac no longer installed spare tires, but it came with a compressor that provided foam to inflate the tire in the event of a flat tire. In February 2010, the consumers wife had a flat tire. A passerby stopped and tried to inflate the tire using the compressor and foam, the foam went in the tire and came out of the hole. The end result, was no inflation of the tire. The consumers wife had to aaa so the vehicle could be towed. Also the trunk had a leak.

- Crawfordville, FL, USA