The service manager told me I should use only Jaguar oil filters because they have a special valve built into them that others do not. I've heard of others that have a valve that keeps the oil from bleeding out of the engine and filter when the engine is shut off. That way when you start the engine there is already oil in the system and you aren't running "dry" at start up. He didn't know what the valve did but I assume it is for the same purpose as above. I've always used Motorcraft filters and was wondering if anyone knew exactly what made the Jaguar filter different then the rest? I had a report on oil filter comparisons a few years ago but can't find it now. I just remember the Motorcraft's were rated at the top along with one other filter and the Fram's were at the bottom of the list.