For the air parking brake systems, the air venting mechanism of the air chambers may allow mud water etc. to enter the inside of the chambers due to improper design. With mud water etc., it may occur that the air vents are blocked and also the O-rings on the pistons are distorted. These problems could allow air to go into the spring chambers, causing the internal pressure to rise, and as a result of it, the parking brakes would not be fully released, which in the worst case could result in a fading phenomenon. Note: This recall is to include more vehicles in the past recall (case number RJ-0859-0, issued on 1 August 2002).