TheOldHokie
Well-known member
Lifetime Member
Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
You are just digging your hole deeper.The 20W is for like a 20w50 oil, for the 20W part. SAE 20 is just 20 weight oil. Neither above nor on line could I find any spec on VI or a lower temperature spec for it to know what xxw20 it is.
The first number is NOT the grade of the oil. It is for its specification at some lower temperature. The 2nd number in the xxwyy spec is the grade of the oil at operating temperature, e.g. 100 C.
I've read where some of you have called 5w30 oil a 5 grade but acts like a 30 grade at operating temperature. No. It's a 30 grade oil that meets the low temperature spec for a 5 grade and likely has about 140-190 VI.
Look at the J300 table. Column one is the grade number. SAE J300 (2015) defines six winter (W) grades and eight summer (high temperature) grades.
The winter grades are 0W, 5W, 10W, 15W, 20W, and 25W
The summer grades are 8, 12, 16, 20, 30, 40, 50, and 60
An oil that only meets the low temperature requirements is a W monograde - SAE 10W for example.
An oil that meets only the high temperature requirements is a summer monograde = e.g SAE 30
A multi-grade oil is an oil that meets BOTH a high temperature grade requirement and a low temperature grade reguirement. Multigrades are written by concatenating the two grade numbers with the winter grade written first followed by the summer grade - e.g. SAE 10W30.
There is no grade 0, 5, 10, or 15 in the current specification. SAE 10 used to exist but was removed decades ago and as far as I know the others were never defined. Grade 16 was added in 2013 and grades 8 and 12 in 2015. The SAE has provided for a future grade 4 if needed.
Dan
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