Originally Posted by Restrorob
If one keeps their oil changed @3000/3500 miles there shouldn't be any old oil/contaminates to drain back in the pan.
And another thing, The filter would have to be mounted up side down to drain old oil/contaminates back into the pan. Even one mounted on it's side would hold any contaminates unless one never changes the oil to the point the filter is full of it.
Routine maintenance is the key to longevity of anything.....
Amen to that
Why worry about alittle cardboard ? When the filter element itself is made out of paper. The only oil filter I've seen mounted upside down is on the newer Ford diesels
When you replace those, all you are replacing is the element itself, it's on top of the engine