This was one of the front tires on my GT350. This is happening all around the outside shoulder of the tire and has increased with mileage. The tread itself and inside shoulder are fine. A dealer service manager said there's no issue with the tire and that it was caused by "impact damage" and one of the managers from Discount Tire said Michelin probably wouldn't warranty it but agreed to replace the tire at prorated cost anyway. The car is a 2017 and currently has 1300 miles on it. T his is the only tire with this issue.