Toy_Guy

Yes, the oil filter has 2 valves:

The "oil retention valve" is a one-way valve which will prevent the oil from draining back into the sump when the engine is not running. Contrary to popular folklore, the engine does not "drain" its oil when the engine is off. There are additional check valves in the system for the cylinder heads to retain their oil upon shutoff.

The "bypass valve" is a pressure relief valve which will allow the oil to flow even if the main filter element is clogged. A safety measure.

Which aftermarket filters have what? I don't know. I'm willing to buy OEM fron Clair and not worry about something so trivial.

vrsix

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Canton Mecca Oil Filter..

Has Anti-drainback valve (or you can set it up for full-flow).

Doesn't have bypass valve. The CM filters flow at such high rates they don't require bypass valves. This means all oil is filtered all the time.. no dirty oil reaching the turbos. Of course, if I weren't using synthetic which stays liquid at very cold temperatures.. I wouldn't trust not having a bypass valve.. but in my opinion.. you can't get a better combination than a CM and synthetic oil.

Oh.. did I mention they filter down to 8 microns, whereas typical filters only filter down to 20 microns. May not sound like a big difference, but I remember seeing SAE reports on the big difference in engine wear between 10 micron dirt and 15 and 20 micron dirt.

vrsix

I now have almost 30k miles and I've had this thing one since about 5k miles and been through two driving schools with it. I change the element and the seals every oil change. Never a single issue. Love it love it love it.

SmokinS4™

Bosche version $5.50 same thing