Yet another oil thread

[nathanVY]

Wasn't full synthetic, semi synthetic. Nah not saying that at all but maybe it would've turned out differently if I'd used thicker oil?

Not sure exactly what the problem is yet but it's got me worried.

 

[Krilnik]

Penrite don't make a semi synthetic 15w 50.

You must be referring to the 15w60 "extra ten" HPR15 oil which i think will now be the way to go for my next oil change.

 

[monkeys437]

I use Nulon synthetic 10W40 in my VS l67 and have done for the last 100k. Its got 250k in total and still going good. Some say its way too thin but I think the trick is regular changes. My oil rarely sees 10k or 6 months whereas i know people that go years and years between services. If there are any issues from running oil this thin im yet to see them

 

[Bourbonated]

I use the HPR15. The first time I put it in my car, it chewed it (Newcastle -> Melbourne = Gone) Since then, it's been through maybe 2mm on the dipstick and it's time for another oil change.

 

[nathanVY]

yeah same diff lol.

 

[The1]

SAE is the oil ratings standard at which our oils are measured against, for EG 20W 50 which is the measurement of COLD pumping and
cranking at a certain temperature point, then the second number is Viscosity rating @ 100 Deg C.

Cranking and Pumping are measured in centipoise, the oil has to meet certain measurements to achieve a rating number.

The Second number is measured in Kinematic centistokes, this is measured @ 100 Deg C and has to meet a MIN and MAX range to determine
it's rating number.

Centipoise as i understand it is related to centistokes, 1 poise of fluid has the density of 1 gram per cubic centimeter and the
kinematic viscosity of 1 stoke, 1 stoke is 1 centimeter squared per second.

So For eg the stock oil 20W 50

20W(Winter or Cold) Rating is 4500 centipoise @ -10 Deg C While Cranking and 60,000 centipoise @ - 20 Deg C while Pumping these are MAX
ratings, if it was a higher centipoise number it would then go into the 25W Viscosity Grade. So 20W oil when @ -10 Deg C Cranks oil at
4500 centipoise, which is 0.04500 grams per cubic centimeter and moves @ 0.04500 centimeters squared per second.

50 Rating is 16.3 Centistokes MIN @ 100 Deg C and 21.9 Centistokes MAX @ 100 DEG c. so the oil flow will be between 0.163 & 0.219
Centimeters squared per second @ 100 Deg C, outside of this range then will cause oil shear or stress.

So to those people running 60 Rating oils it will be 21.9 Centistokes MIN & 26.1 Centistokes max so the oil flow @ 100Deg C will be
greater.

Also the Different winter grades remain relitivly the same measurements, just the temperature drops so the viscosity that 15w achieves
while cranking @ -15 Deg is the same as 10w but while cranking at -20 Deg C, so this may mean different centipoise figures above these
temperatures So a Low W number may aid in cold starting even though the oil is not at negative whatever..

0W -30C Crank -40C Pumping
5W -25C Crank -35C Pumping
10W -20C Crank -30C Pumping
15W -15C Crank -25C Pumping
20W -10C Crank -20C Pumping
25W -5C Crank -15C Pumping

Hot Ratings MIN MAX @ 100 Deg C
20 5.6 9.3
30 9.3 12.5
40 12.5 16.3
50 16.3 21.9
60 21.9 26.1

Here's a handy calculator
Calculator

So now you can go onto your oil brands website download there spec sheet and compair it against a competitors oil to check there cold and
hot ratings. Note i may have some calculations wrong please correct me, it's all on the net & books anyway.

 

[ben315vz]

I use Mobil 10w40 Semi Synthetic oil in my VS (ecotec V6) and WH Statesman (ecotec V6) and never have had a problem. VS has done 300,XXXkms and i service it every 5,000kms.

 

[HOLDENFAN]

in my opinion id be running something a bit thicker in an ecotec with that many km's, Over 200kms I would use a minimum of 15w40, and over 300 id be looking at a 20w50 or the Penrite HPR15 at least.

 

[The1]

i dont get what your trying to achieve using a non standard oil though?

 

[HOLDENFAN]

i dont get what your trying to achieve using a non standard oil though?

off the top of my head for the buick V6, holden recommend a 20w50 oil, or for cold climates, a 15w30(or40). Oil quality has changed alot in the last 15 years or so i've read recently, and due to that alot of oils that were available are becoming redundant (20w40 being one of the most popular, as newer 15w40 does essentially the same job). Same as now 15w60 (the hpr15+ i believe),i've seen used alot on forums recently whereas 10 years back things like w60 grade were only generally used in older engines that used a fair bit of oil. Using a thicker oil in older engines can be beneficial for obvious reasons, (we've all read stories of people trying to put mobil 1 and such in there older engines and they leak and use oil), having a better thickness at operating temperature. I guess if your engines not leaking or using oil, there's no real reason to go to a thicker oil, but with todays climate and traffic conditions, cars getting hotter and so on, going to a slightly higher grade oil wont hurt your engine at all.