Motor oil is full of impurities from its production process. The original oil filter in your BMW i3 with range extender catches and removes them. Without it, your EV's engine would fill up with gunk. The best way to prevent this is by regularly replacing yours with a genuine BMW i3 oil filter. It'll keep your engine in top-performance shape. However, even a high-quality BMW oil filter decays with age or clogs with crud eventually. That can negatively affect how well your sedan's engine works and cause parts like your oil pump and bearings to wear out much more quickly. Luckily, when to change an oil filter is easy to remember. Do it at every oil change, which is every 3,000 miles or every few months, whichever comes first. Pay attention to which oil filter your BMW i3 uses, however, because oil filters differ by gasket and thread sizes. You don't want to use the wrong one. An oil leak can result, or the filter can detach completely, and that'll mean major engine damage. Your best option for proper fitment is to stick with a factory BMW i3 oil filter. It'll be compatible with your electric vehicle right off the shelf. You can even order new oil filters online, right from our auto parts store. Buy now and check that replacement project off your list!