2008 Mercedes C-Class Owner's Manual - Page 342

Operation Tires and wheels Checking tire inflation pressure Regularly check the tire inflation pressure at least once a month. Check and adjust the tire inflation pressure when the tires are cold. The tires can be considered cold if the vehicle has been parked for at least 3 hours or driven less than 1 mile (1.6 km). If you check the tire inflation pressure when the tires are warm (the vehicle has been driven for several miles or sitting less than 3 hours), the reading will be approximately 4 psi (0.3 bar) higher than the cold reading. This is normal. Do not let air out to match the specified cold tire inflation pressure. Otherwise, the tire will be underinflated. Warning! Follow recommended tire inflation pressures. Do not underinflate tires. Underinflated tires wear excessively and/or unevenly, adversely affect handling and fuel economy, and are more likely to fail from being overheated. Do not overinflate tires. Overinflated tires can adversely affect handling and ride comfort, wear unevenly, increase stopping distance, and result in sudden deflation (blowout) because they are more likely to become punctured or damaged by road debris, potholes etc. Do not overload the tires by exceeding the specified load limit or total load limit as indicated on the Tire and Loading Information placard on the driver's door B-pillar. Overloading the tires can overheat them, possibly causing a blowout. Overloading the tires can also result in handling or steering problems, or brake failure. Remove the cap from the valve on one tire. Firmly press a tire gauge onto the valve. Read tire inflation pressure on tire gauge and check against the recommended tire inflation pressure on the Tire and Loading Information placard on the driver's door B-pillar ( page 334) or, if available, the supplemental tire inflation pressure information on the inside of the fuel filler flap ( page 322). If necessary, add air to achieve the recommended tire inflation pressure. i If you have overfilled the tire, release tire inflation pressure by pushing the metal stem of the valve with e.g. a tip of a pen. Then recheck the tire inflation pressure with the tire gauge. G Install the valve cap. Checking tire inflation pressure manually Follow the steps below to achieve correct tire inflation pressure: Repeat this procedure for each tire. 341