2009 Mercedes SL-Class Owner's Manual - Page 219

Operation Tires and wheels Rlead to tire failure from being overheated affect handling characteristics Checking tire inflation pressure Safety notes G 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 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. Check the tire inflation pressure at least every other week. Radversely Overinflated tires G Warning! Follow recommended tire inflation pressures. 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. Overinflated tires can Radversely Rcause Rbe 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. Checking tire inflation pressure manually Follow the steps below to achieve correct tire inflation pressure: X Remove the cap from the valve on one tire. X X affect handling characteristics uneven tire wear more prone to damage from road hazards affect ride comfort stopping distance Firmly press a tire gauge onto the valve. Read the tire inflation pressure on the tire gauge and check against the recommended tire inflation pressure on the Tire and Loading Information placard on the driver's door B-pillar (Y page 212). If necessary, add air to achieve the recommended tire inflation pressure. Radversely Rincrease Z 217