<VV> A slightly corrected part 2
BobHelt at aol.com
BobHelt at aol.com
Sat Sep 20 01:33:01 EDT 2008
NON GF-4 OILS
Non GF-4 oils are all the other viscosities. That includes, for example,
10W-40 and 20W-50. These oils are all rated SM (latest rating). The letters SM
will be stated in the top portion of the donut on the back of the container.
Since these oils might include racing, high mileage or diesel categories, the
committee set the following phosphorous requirement for all of these oils. A
minimum SM phosphorous requirement of 600 ppm, and any amount of phosphorous
greater than the minimum for the upper limit. There is NO phosphorous upper
limit in the specification. But of course an application limit will be set by
the oil producer. Again, there is no requirement of any zinc content either.
There will be no Starburst or “energy conserving” on these containers.
OVERLAPPING RATINGS (E.g. SJ/SM or CI-4/SL)
Here is where the confusion begins. Let’s look at some examples. Consider an
SM rated 10W-30 oil (or 5W-20 too). Here we have conflicting specs. 10W-30 is
a GF-4 oil with reduced phosphorous but SM has no upper limit. So the GF-4
spec takes precedence and establishes the upper limit of 800 ppm. (The SM spec
upper limit is simply any amount greater than 600 ppm.) Thus, this amount of
phosphorous (anything over 600 ppm) meets the SM spec.
Now consider a 20W-50 oil with an SJ/SM rating in the donut. SJ has an upper
phos. limit of 1000 ppm and SM has no upper limit. So this oil will have a
maximum phos. Of 1000 ppm. But what if this were a 0W-20 oil with these
ratings? It would require that the GF-4 spec be met with an upper limit of 800 ppm
phos. despite the SJ/SM ratings.
Similarly, CI-4/SM in the donut (a diesel oil) will have 1400 ppm phos.
since this will also meet the SM spec of no upper limit.
But to be sure we cover all bases, let’s look at an oil rated CI-4/SL.
(Another diesel oil). Here is where the specs cause problems. The upper phos limit
of CI-4 is 1400 ppm but the upper limit of SL is 1000 ppm. (Note that the
CI-4 1400 ppm is an upper limit and not a required amount) So an oil with both
of these rating will have no more than 1000 ppm phos. to meet the SL
designation and still will meet the CI-4 spec.
Regards,
Bob Helt
**************Looking for simple solutions to your real-life financial
challenges? Check out WalletPop for the latest news and information, tips and
calculators. (http://www.walletpop.com/?NCID=emlcntuswall00000001)
More information about the VirtualVairs
mailing list