When I take the oil filter out it drips old oil back
in the oil filter housing, so if there is already
new oil in the the crankcase it will be mixed
with what drips from the old filter. I can't
imagine it really matters if you take the oil
filter out while the drain plug is removed,
and give it a few more minutes to drain.
A word about oil coolers-I've read that the
threads can be easily stripped since the oil
cooler is made of a soft metal. I wonder also
that the empty cooler will take time to fill up...
does that mean the engine will be w/o oil
pressure for that time? I think similiar benefits
to an oil cooler drain can be acheived with
frequent oil changes.
Mark 82'300Sd 280k