A lot of good info thrown out here...........thanks
I discovered a few years ago about the API index or grading & JASO
The further down the alphabet the better the oil as syn. goes the furthest.
Wmt. has a ........SAE 5W 20 Full Syn oil API SP Plus ISLAC G5 under $15
I personally use SAE 5W 30 Full Syn High Mileage etc.
I recommend MOTORKOTE:
(reason I believe NASCAR engine's don't blow up anymore unless someone forgot to put it in)
Found MK when my 7 yr warranty ran out on a new $30k Hi Perf Harley I bought in 2007. There are 73k on the bike now with literally no internal noises at operating temp. If I remember correctly H-D wanted $1800 for 2 more yr's.
EDIT ADDED: NO INTERNAL NOISES USING A MECHANIC'S STETHOSCOPE ALL AROUND THE OVERALL BLOCK (RUNNING).
ADDITIONAL CREDIT GOES TO QUICKSILVER 20W 50 FULL SYN (PARAFFIN BASED) MOTORCYCLE OIL.
Now look at what you guy's made me find !
(Recommend viewing complete article below)
en.wikipedia.org
The International Lubricant Standardization and Approval Committee (ILSAC) also has standards for motor oil. Introduced in 2004, GF-4
[22] applies to SAE 0W-20, 5W-20, 0W-30, 5W-30, and 10W-30 viscosity grade oils. In general, ILSAC works with API in creating the newest gasoline oil specification, with ILSAC adding an extra requirement of fuel economy testing to their specification. For GF-4, a Sequence VIB Fuel Economy Test (ASTM D6837) is required that is not required in API service category SM.
A key new test for GF-4, which is also required for API SM, is the Sequence IIIG, which involves running a 3.8 litres (230 cu in),
GM 3.8 L V-6 at 125 hp (93 kW), 3,600 rpm, and 150 °C (302 °F) oil temperature for 100 hours. These are much more severe conditions than any API-specified oil was designed for: cars which typically push their oil temperature consistently above 100 °C (212 °F) are most
turbocharged engines, along with most engines of European or Japanese origin, particularly small capacity, high power output.
The IIIG test is about 50% more difficult
[23] than the previous IIIF test, used in GF-3 and API SL oils. Engine oils bearing the API starburst symbol since 2005 are ILSAC GF-4 compliant.
[24]
To help consumers recognize that an oil meets the ILSAC requirements, API developed a "starburst" certification mark.
A new set of specifications, GF-5,
[25] took effect in October 2010. The industry had one year to convert their oils to GF-5 and in September 2011, ILSAC no longer offered licensing for GF-4.
After nearly a decade of GF-5, ILSAC released final GF-6 specifications in 2019, with licensed sales to oil manufacturers and re-branders to begin 1 May 2020. There are two GF6 standards; GF-6A being a progression and fully backwards compatible with GF-5, and GF-6B specifically for SAE 0W-16 viscosity oil.
[26]