Location

• The oil filter on your 325i is positioned at the front of your engine block. The filter is located directly between the fan and the valve cover, to the right of center and to the left of the air intake hose. You will see two cylindrical components with rounded caps, similar to the cap for a PVC pipe. The oil filter cap is the one on the left.
  
  

Filter Cap

• The actual oil filter on your 325i is held inside this filter housing or cap. To access the filter, remove the filter cap using a wrench. Once you remove the cap, slide the oil filter off the tube that extends from the cap housing.
  
  

Recommended Oil

• BMW recommends using only high-performance, synthetic 10W40 or 10W30 oils in your 325i. When changing your oil filter, you will need 7 quarts of oil, as your 325i's engine capacity is 6.9 quarts.