Changed the oil, but not the filter...

[jeeperguy21]

This isn't exactly an XJ question, but I think it could be applied to it as well...

My wife's DD is a 2007 Mazda 6. I always change the XJ's oil myself, so I figured that we should stop throwing money away by having someone else change the Mazda's as well.

Me being the "special" person that I am, assumed that the Mazda oil change would be just like any other vehicle oil change... but come to find out (after I had drained out all the old oil) the oil filter requires a special tool from the dealership to remove. It has a drain plug on the filter, but requires a special filter wrench to remove since it is not a standard filter, unlike the filters on the XJ which just twist on.

In my effort to be efficient, I started this oil change at about 8:00 PM last night, so the stealership was closed, and no auto parts stores carry this tool.

My wife had to take the car to work this morning, so I ended up just putting new oil in the car without being able to change the filter. My question is, after I get the special tool to remove the old filter later today, I was planning on giving it a whole other oil change, even though a lot of the old oil had drained out of the filter.

Is this overkill? Should I just swap on the new filter and call it good because it will have only have been driven for a half hour or so, or should I go ahead with my original plan and change the oil again?

Not a whole lot of info on the internet about changing the oil but not the filter. It's usually the other way around for the nutjobs that try to get 10k+ between oil changes. Thanks for any input.

 

[shanesaw]

Just change the filter and call it done. You probably have .0001% old oil mixed with the new oil. That will not significantly affect your engine in any manner.

 

[kastein]

What position is the filter in? If it's open end up, I'd do a whole change personally, though only the amount of oil in the cavities above the filter + the filter itself is old oil.

Also, I hate those stupid "special tool" filters, half the time it's some flimsy plastic screw-in cap thing that breaks if you look at it funny and loves to cross thread. It got to the point that we kept spare filter housings on hand at the quicklube I worked at (not a jiffy lube) so that if we broke one, we could give them a new one free and send them on their way instead of having to hold their car and run to the dealership real quick.

Making oil/coolant components of out of plastic (*cough* heater control valve *cough*) has got to be one of the most wrongheaded, cost-not-quality based ideas I have ever seen. Damn bean counters...

 

[joe_peters]

I would just change the filter.

80s Volvos had an oil change interval of 3750, but the filter was only supposed to be changed every 7500 miles. Our dealership policy required changing both, so we did, but Volvo's engineers saw it different.

 

[birchlakeXJ]

I would just change the filter.

Me too. Don't overthink this; you'll be fine.

 

[winterbeater]

X# - change the filter. Run it a day and look at the oil color. It should tell you that you are good.

But don't go by what I say. I'm a nutjob.

 

[96XJ_4.0]

Run a day?

4 quarts of oil at 50psi through 1/8inch+/- diameter passages should yield gallons per minute (s).

I would change the filter, run it 5 minutes, and check the oil color. If it looks like ANY OLD OIL IS IN THERE... in my opinion alone; I would say change the oil.

 

[winterbeater]

He's gonna have 15-20% old oil. That is a given.

 

[cruiser54]

Just shorten up the interval til the next oil change by 15 to 20% then, if you're gonna be concerned at all.

 

[heyhar]

It's sorta like taking a shower and putting your used underwear back on. You're cleaner, but... Assuming that you change the oil more often than the factory schedule, do the filter and call it a day.

 

[Joshooha]

you don't need to waste your money on a mazda special tool. You can get a screw driver and tap that casing loose. But if you are not confident in your strength then I would get the damn tool, you can crack those cases pretty easily.

 

[joe_peters]

He's gonna have 15-20% old oil. That is a given.

Well, lets think about this.

If he had a quality oil filter on his 4.0, the filter would retain 1/2 quart out of 6 quarts total--right? So, that would be 8.33 % old oil.

Now, if he is smart and running a Wix 51515 filter, that would give him 1 quart out of 6.5 quarts total--right? So, that would be 15.38 % old oil.

Ok--follow closely here--if he was using a cheap-a** filter with a nitrile rubber anti-drain back valve that has FAIL as its standard condition then there wouldn't have been any oil in the filter, and he would be as close to 100 % new oil as you are going to get--right?

Two soft chewy chocolate chip cookies to the first person that can name a major oil filter manufacturer that still uses nitrile rubber anti-drain back valves in their best selling economy filter--ready, set, go!

 

[kastein]

Non jeep question actually... should be in other tech I guess :dunno:

It's one of those infernal plastic case screw in things that you snap a new filter element onto every time you change the filter, as I understand it. So there is no drainback valve, at least not in the oil filter. If the plastic case thing hangs off the bottom of the engine like I think it will though, it'll hold oil regardless of a valve being present.

 

[JNickel101]

Fram?

 

[winterbeater]

Fram, bam, thank you Ma'am!

 

[joe_peters]

Fram?

Do you want your cookies shipped or will you be picking them up in person?

 

[Matthew Currie]

Well, lets think about this.

If he had a quality oil filter on his 4.0, the filter would retain 1/2 quart out of 6 quarts total--right? So, that would be 8.33 % old oil.

Now, if he is smart and running a Wix 51515 filter, that would give him 1 quart out of 6.5 quarts total--right? So, that would be 15.38 % old oil.

Ok--follow closely here--if he was using a cheap-a** filter with a nitrile rubber anti-drain back valve that has FAIL as its standard condition then there wouldn't have been any oil in the filter, and he would be as close to 100 % new oil as you are going to get--right?

Two soft chewy chocolate chip cookies to the first person that can name a major oil filter manufacturer that still uses nitrile rubber anti-drain back valves in their best selling economy filter--ready, set, go!

I thought it was impolite to use four letter F words here.

 

[joe_peters]

I thought it was impolite to use four letter F words here.

You mean the ones that begin with "F"? :jester:

 

[1990heepxj]

ill name one that uses a nitrile diaphram: mobile 1. actually one of few to not use nitrile is frams best kind the tough gaurd which uses silicone rubber

 

[joe_peters]

I just made this one up:

Why does "F" have so many different models of oil filter for the same application?



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