This oil is solid particles (the same black, metal shavings, or rather, metal dust). By installing a new filter, you filter out all that garbage. Otherwise, he (with fresh oil) through a safety valve clogged filter will fall on the old pads and it establishes a presence in the aluminum liner material. Did you know that the stones sawing copper disc, which introduced the diamond dust? And inserts embedded in them with solids (garbage) will be 'cut' a neck crank. In addition, it is unclear what will happen as a result of the interaction of the new oil with the remnants of the old in the filter. Maybe it will curdle, and received 'jelly' (a two hundred grams of it would be, no less) to score any channel.
It is therefore necessary when changing the oil and filter change. How often to change oil? Recommendations on terms of replacement instructions are provided in the vehicle. We can only recall the need to take into account the real operating conditions, which, unfortunately, are far from ideal. Most drivers will be surprised when they learn that an example of driving in difficult conditions is a small an elderly lady who goes to his car once a week on the weekend on the market. But it's true. It should change their oil more frequently than truck drivers and riders. The problem is that when riding a short distance, the intense driving with frequent stops and driving in cold weather, the engine does not have time to warm up enough to vaporize the water and fuel that are deposited in the oil.