Today I changed the oil in my new-to-me C32 for the first time. I used an oil extractor, Mann fleece filter, Mobil 0W-40 and a filter cap wrench I found at Schuck's auto parts. By far the easiest oil change I have ever completed, though the claims I have seen on this forum of being able to do it without getting your hands dirty seem impossible considering what is necessary to swap out the oil filter. This leads to the question: Is it necessary to replace the O-rings when changing the oil filter?

All the O-rings on my filter 'stalk' or 'holder' or whatever it is properly called seemed pliable and undamaged. I briefly considered reinstalling them with the new filter before reconsidering and pulling them all off and replacing with the new ones contained in the Mann filter kit. Anybody ever re-use the old O-rings?

On a side note, my Mann filter kit came with five O-rings but there were only four old ones and only four O-ring lands I could find. Did I just get an extra O-ring or did I (and the last technician to change the filter) miss one?

They come with the filter, just replace them. Why not? Different cars will use different combinations of the O rings, not all of them may be used for your car.

I am of the 'if-it-ain't-broke-don't-fix-it' school of thought, so I considered leaving them alone since they seemed perfectly serviceable. The idea of keeping my hands clean appealed to me somewhat as well. Ultimately I chose to replace them.

That makes sense and makes me feel better. Thanks!

i would just replace them..but i have done one without replacing it and it was fine until the next oil change. But i do oil changes a little early, around 7000 miles.

Right, I would usually agree with you. But just like the oil and filter you're replacing, they included the O rings for a reason. I mean honestly, you could take that approach and just not replace your engine oil until it siezes. Buy some rubber gloves, replace the O rings at each oil change. Just my opinion.

It's your first time changing the oil, so you should change it. Who knows if the last person that changed the filter didn't replace it. The last thing you need is for it to start seeping oil IMHO.

You must replace the o-rings or the fiter housing will leak.

Good idea to change them and you used 4 out of the 5 rings because the last one is for the oil pan underneath the car. But you used an extractor so you are good to gooooooooooooooooo..lol

I wondered this myself since my o-rings also looked to be in great condition. But in the end, who cares, it's a serviceable part meant to be changed when serviced, so go ahead and change them. You paid for them didn't you?

The "if it ain't broke don't fix it" clause doesn't apply when it comes to preventative maintenance.

so the oil is drained, old filter is out and new filter in hand.....why are we having this conversation? at that point, its ten seconds more