Oil Filter - Drain-Back Check Valve
 

The MAHLE oil filters I had been using apparently have a drain back check valve in the filter body. At least I think that is what I see, but the MANN filters don't seem to have this feature.

I had though BOTH were anti drain back filters. Are they? Or do I not understand what I am seeing.

It really doesn't matter....
 

The filter on the AAN sits in such a way that oil cannot drain back out of it. On other Audi applications, like my A6, it is necessary to have an anti-drain back valve to prevent oil from escaping back into the pan, due to the angle of the filter (approx 45 degree angle). Sure, having one is nice I guess for whatever reason we want to believe, but fact is it's pointless on our cars.

2nd.. Put yur $$$ into the best damn filter you can get. I use Mann. (Mahle is a great 2nd)

as repeater stated, it isn't required, but is nice to have
 

It is for when the engine is shut down, it could end up sucking the oil filter dry in the last few seconds, or the filter could leech back into the pan, but since our filter are vertical, it isn't too important.

Related question for you guys
 

When you do an oil change, do you fill up the filter with fresh oil before you spin it on? I do.

Yes.
 

If you don't, the engine is oil starved for 3-4 seconds while the filter fills up.

And if you have to use domestic.....
 

Baldwin or Purolator Pure One

And if the only filter available is orange - park your car.

Yep, except the new tough gards are not a bad filter...
 

They've gone to a metal cap on the filter element and are running nitrile gaskets and drain backs in them. They are much, much higher quality that the cheap-o Frams.