Review on PH6941 Extra Guard Passenger Filter by William Mahajan

With a 20x1.5mm thread, this oil filter can be used on various Asian vehicles. It's mainly used on Porsche vehicles, so you know it needs to be manufactured to a high standard. I used a KandN #4001 oil filter, but this fram is a few inches longer and doesn't have a bypass relief valve that circulates a lot of dirty engine oil. This fram filter is actually a drag racing filter as it does not have a bypass valve so the engine always gets a full amount of freshly filtered oil. The bursting pressure of the can is also higher. This is particularly beneficial for those who use a very light oil such as 5w20 or 0w30 in their engines as it will pass through the oil filter very easily even at low outside temperatures. However, as a precaution, I would only accelerate strongly when the engine oil is at operating temperature so that the oil can flow through the filter element without any problems. And it is imperative that this filter does not clog as there is no by-pass valve; This means the oil filter doesn't need to be driven more than 5,000 miles to be safe. If you want to drive 15,000 miles, this oil filter is not for you. I am very happy with the oil filter and its comfort knowing that my engine is cleaning oil all the time, not just a percentage.