Hi All, I have been pondering my choice of oil for the CLK as the car is now nearing 95k miles and is using around 1/2 litre every 1000-1250 miles. I am unsure from when I bought the car whether it had synth or semi synth so I have been topping up with Mobil 1 229.5 spec. Now its time for a change and I am wondering whether putting semi in will reduce the amount of oil its using? Its that or stick with Mobil 1 and keep an eye on the top ups. Any suggestions please?