Infinite Space Systems, Inc. wrote:
John,
I followed your postings on zinc and phosphoros additive for motor oil a
while back. I use the GM stuff myself. I am courious as to what years this
is necessary
to keep engine wear to a minimum. thru the 80's into the 90's?
thanks
Personally, I'd tell the EPA to go to Hell and use an oil that has healthy
zinc and phosphorous additives in any engine, regardless. API SJ grade oils
still have very healthy zinc and phosphorous content, while SL and SM grades
had the content reduced greatly, respectively. SJ grade is listed for
engines in 2001 and older. SL is for 2002 to 2004. SM is 2005 and
later.That's the giveaway this issue is all about emission politics and not
about science and engineering. So far, all the studies done to prove zinc
and phosphorous will harm catalytic converters have been inconclusive. In a
couple of engineering tests, there was evidence that zinc and phosphorous
actually improved the catalytic converter efficiency. But the EPA wants
those 2 additives gone, for it will mean older engines will eventually die,
which is exactly what the EPA empire wants. Older engines and cars can't be
banned by law, for the U.S. Constitution forbids it.
Hi All,
Milton, FWIW, When I was researching this topic I found info that said
the manufactures were the ones who asked for a reduction in the ZDDP
additives.
The reason stated was that those additives were leaving a film on the o2
sensors. It made no mention of the cat converters. The new emission laws
requires the manufactures to cover emissions equipment for 100k miles.
And the film was causing early failures.
Whatever the reason, I agree with using a oil with a high ZDDP on all
engines.
Joe Walters
73 H/O
