SAE 5W-20 or 0W-20? - GreenHybrid

vioarc · #1 (**permalink**) 08-16-2006, 04:41 PM

Why 2?

TKCamry · #2 (**permalink**) 08-16-2006, 05:16 PM

Quote:

Originally Posted by vioarc

Why 2?

Weather. 0w-20 better for very cold climates in winter.

vioarc · #3 (**permalink**) 08-16-2006, 05:30 PM

Thanks for the reply.
Living in Kennessee (just north of I-40) the 5W-20 should do here year-round.

kluken · #4 (**permalink**) 08-17-2006, 04:20 AM

When I do my first oil chaneg i will be going with 0W20 and I am in Atlanta. Regardless of climate 0W20 will get through the engine faster during startup than 5W20. With all the stopping and starting of the engine I figure it will only benefit the engine in the long run. And for Mobil1 all the grades are usually the same price. The difference is if you go with 5W20 you can get non-synthetic and save $$, but as i only use synthetic it is no difference to me to use 0W20.

zadscmc · #5 (**permalink**) 08-17-2006, 05:10 AM

The HCH says 0w20 on it, so that's what I give it.

kluken · #6 (**permalink**) 08-17-2006, 05:41 AM

Wow so the HCH basiclaly forces you into synthetic I dont; knwo of an convential 0w20 based oil.

lars-ss · #7 (**permalink**) 08-17-2006, 07:55 AM

0w-20 is better for mileage in any circumstance. Thinner oil means less friction, meaning the engine gets more done on less work.

lars-ss · #8 (**permalink**) 08-17-2006, 07:56 AM

Quote:

Originally Posted by kluken

Wow so the HCH basiclaly forces you into synthetic I dont; knwo of an convential 0w20 based oil.

Honda's 0w-20 is not 100% synthetic, is it? I've never got a good answer to tht question. Some people say it is, some say it's not.

schmidtj · #9 (**permalink**) 08-17-2006, 08:21 AM

Quote:

Originally Posted by lars-ss

0w-20 is better for mileage in any circumstance. Thinner oil means less friction, meaning the engine gets more done on less work.

The "20" is a bigger factor. Once the engine reaches operating temperature the first number is meaningless.
The first number is cold viscosity the second number is hot viscosity.
Since they both have a "20" as the hight temp viscosity I'd say the gas mileage difference is infinitesimal.
Thinner oil at high temperatures means more wear and tear on the engine.
J

lars-ss · #10 (**permalink**) 08-17-2006, 08:43 AM

Quote:

Originally Posted by schmidtj

Thinner oil at high temperatures means more wear and tear on the engine. J

GENERALLY, that statement is true.

But in reality it depends on the protection capability of the oil. The very best synthetic oils are designed with uniform size molecules so that they protect just as well in high heat as under other conditions. They are engineered to defend against thermal breakdown.

Quote:

Mobil Oil recently reported the results of simulated hot-weather
performance with its Mobil 1 synthetic as evaluated by a standardized,
grueling engine test known as the Olds III-D. In this test, an
Oldsmobile 350" V8 engine is run for 64 hours at a 100-hp load and 300F
crankcase oil temperature. This test is designed to measure an oils
ability to resist oxidation and evaporation (and consequent thickening)
at high temperature. (If it seems odd that oil would *thicken* at high
temperature, consider the analogy of heating a pan of cold syrup on a
stove. At first it would become quite thinner, but if left for, say,
several hours, the resultant evaporation would cause the syrup to become
progressively thicker.) In order to qualify for the American Petroleum
Institutes top "SF" rating, a motor oil must pass the III-D test. This
means that it can thicken to no more than 375% of original viscosity at
the end of 64 hours of continuous running. Mobil states: "To test the
extra stability provided by the Mobil synthetic oil, we decided to run
the III-D *for 128 hours*...double its normal length...and without oil
drain. The Mobil 1 synthetic easily passed the test under these brutal
conditions, thickening only an insignificant 20%. For comparison, a
high-performance premium conventional oil was tested under identical
conditions. That test had to stop at 96 hours; the oil had turned
solid. Another premium conventional oil forced the the test to stop at
112 hours, well before the end of the scheduled double length." Amoco
Conducted an identical double-sequence III-D test on its Ultimate 5W-30
synthetic; it also passed the test with flying colors, thickening only 18%

So the thinner synthetics do perform way better at high temps.