Re: how much to change the oil

["Mudry, Robert (CAP, AMR)" <rob.mudry@xxxxxxxxxxxxx>]

Christopher snaps at Jim Ochi...

Jim,I appreciate your desire to invote lurkers to respond but please only
postgood information.To my knowlege there is really no debate as to how
often to change oil - it'ssimple, the more you change the oil, the less wear
from abrasives andcontaminants. This is not a subjective/opinion/x/y axis
answer, the more youchange the oil the longer the engine will last - PERIOD.
This is with allother condions equal. There are no conditions where changing
the oil lessfrequently will allow an engine to last longer.I think the
debate circles around the economics of changing oil. There willnever be a
resolution to this because each individel's fact pattern isdifferent. The
person who leases may only find it meaningful to change theoil enough to
maintain his lease obligation, but the person who has anemotional bond to
his new M3 may want it changed when it starts looking lessthan clean.I want
all the fluids in my car to look new, I don't really care if it has aneffect
on how long the piece lasts or not, I simply enjoy looking into thecoolant
tank or power steering reservoir and seeing spanking clean
syntheticfluid.Talk about tribology if you want, I change the oil because it
makes me feelgood.
Christopher

<< 5. Some people follow the Service indicator lights for oil changes
(usually this means that they have an oil change every 7500-9000 miles).
Others change every 3000-3500 and ignore the lights. Big debate about what's
better, no definitive answer. Jim Ochi jochi@domain.elided >>

Christpher,

So you think it's that simple, eh?  I would have to disagree with you on
that one.  Your response started out pretty good.  You've made several
claims on how the frequency of the oil change is the only contributing
factor to engine wear.  I was getting really into your post, hoping to read
some real good facts behind this, or perhaps even examples.  But no, you
don't give any.  Just because you like seeing clean fluids in the car, it
doesn't mean that's the reason why it extends the life of the car.  Let me
give you an example.  My dad is probably one of the worst drivers in the
world.  He loves to lug the engine and changes the oil once or twice a year
with whatever is on sale at Walmart.  I believe he may also even change the
oil filter every other oil change.   His '88 Honda Civic has 190K miles
right now.  He doesn't do anything to the car.  He still got the original
timing belt.  He went thru 3 exhaust systems, one clutch, and recently 2nd
change of brake pads.  He might have changed the cooling liquid once or
twice. He never bled the brakes as far as I know.  But the car still runs
like a champ.  I drive the car around town whenever I'm at my parent's
house, and it just boggles my mind!  (well, the front wheel bearings are
starting to go...)

Anyway, I used to change my oil religiously every 3k mi in my '89 Mazda MX-6
GT with Mobil 1 synthetic.  I knew that the engine would run for ever and
ever and I'm sure the current owner of the car really appreciates that.  So
my point is as follows.  Sure, frequent oil change may or may not increase
the life of the engine.  I agree with Jim Ochi on that one - it's an open
issue.  But who cares?  How many people on this list keep their cars until
the engine dies?  Am I gonna keep my 328is until it dies?  No way!   I'll
probably be shopping for a new car around the time E46 M3 comes out.  In the
mean time the factory warranty will carry me way into 2000.  So I'll
continue changing my oil whenever the indicator tells me (or perhaps even a
little sooner - depends on how bored I am)  with Mobil 1 synthetic.  It's a
very personal issue.  Whatever makes you feel good/happy...

Rob Mudry
'96 328is
BMW CCA # 135536

PS.  My dad is a senior mechanic in charge of huge 3,300 BHP @ 900 rpm
Caterpillar diesel engines on an oil rig down in the Gulf of Mexico.
Perhaps he knows something we don't...
  

------------------------------