I'm investigating the use of royal purple oil in my 8, and I know that the oil can last longer than 3K, if, you change the filter. I've never just changed a filter and not the oil, so I'm trying to figure out how you can do this without the oil going everywhere (I know our filter points up rather than down, so that helps).

Has anyone done this? Have you gone 6k miles on your oil with a filter change at 3K and fill ups? Can you change the filter with the oil in the pan, will I have to worry about oil leaking out places other than the filter when it comes off?

If you're already yanking the filter off, is it really that painful to change the oil while you're at it. I've heard of changing the oil without the filter, but never the other way around.

I'm investigating the use of royal purple oil in my 8, and I know that the oil can last longer than 3K, if, you change the filter. I've never just changed a filter and not the oil, so I'm trying to figure out how you can do this without the oil going everywhere (I know our filter points up rather than down, so that helps).

Has anyone done this? Have you gone 6k miles on your oil with a filter change at 3K and fill ups? Can you change the filter with the oil in the pan, will I have to worry about oil leaking out places other than the filter when it comes off?

I know what your're getting at since this is done by people with piston engines to double the oil change interval when running synthetic oil. Especially if you do alot of highway miles. There is a couple of things you need to consider.

When you change the oil in the 8 you only really replace a little over half the oil, the rest stays in the oil coolers. If fuel dilution is an issue in your car this could be a concern.

If you do mostly short trip city driving and go by miles alone to change your oil, it may be a long haul between oil changes. Short trips, where the car barely reaches normal operating temperature, are hard on your oil. Short trips also increase the probability of fuel dilution.

There have been people on this forum who have had their oil analyzed. That is probably your best bet to insure that the oil change interval you want to implement is OK for your car and driving conditions.

As far as removing the filter with oil still in the pan, that is not a problem. You should top off your oil afterward to compensate for the amount left in the old filter.

Synthetic Oil, it that safe to run. Isn't the engine design to burn off x-amount of oil. Would that be effected?

If you're already yanking the filter off, is it really that painful to change the oil while you're at it. I've heard of changing the oil without the filter, but never the other way around.


synthetic oil isnt cheap, and lasts 15k between changes (well, at least red line, not sure about rp) so it wouldnt be smart to do a change


as for the original question, just take the filter off and replace it. you will lose some oil, so run it for a minute or so and then top it off