Nissan Motor Co. is recalling nearly 170,000 Sentra sedans in the United States to address a brake cylinder that could leak fluid. The recall involves 2007-2008 Sentras. Nissan said in a letter to NHTSA that an irregularity in some of the cylinders could lead to a gap that could allow fluid to leak into the brake booster assembly. The leak could cause the brake warning light to turn on. Nissan said if the warning lamp is ignored, one of the brake circuits may not operate and could increase the risk of a crash. According to Nissan, there have been no crashes or injuries related to the issue. The Japanese automaker will replace the cylinder, which is made by auto supplier Robert Bosch GmbH, at no additional charge. This is obviously a safety defect and should be taken seriously by all concerned.