OK to use an SL oil ?

[fdcg27]

While I wouldn't go out of may way to find an SL motor oil for your application, I'd use it if I had it laying around.
The metals levels might not even exceed the requirements of the SM oil that's probably recommended for your Chevy since Valvoline oils typically have low add pack numbers aside from sodium.

 

[BrocLuno]

Originally Posted By: kschachn


But it's not a problem today correct? So all the warnings in this thread are no longer applicable? I can still start my old BMW at -25 F with the usual Castrol 0W-40 and not worry?


If you have a 0W anything, it will not have any paraffin base mineral oils. Any separation in a 0W oil would be down at -40*F or colder.

The oil in this thread that the OP was wondering about was made in 2004. That's pretty much a different animal than what we routinely have today.

And it's not a question of "in the sump" - it's a question of prolonged cold in storage with no agitation and re-heating.

The OP has a sound plan. Run it in the spring/summer/fall. 1 gal old oil and top up with modern. That should do it

If this was a question from a poster in Calif or Texas, this would never have come up. But he's in Canada and it can get cold and quiet for prolonged periods, so the cautionary discussion about 12 year old oil ...

 

[gallydif]

Originally Posted By: Mr Nice
I still have some SL rated Mobil 1.

Mobil 1 still makes SL oil. M1HM is SL

 

[pbm]

Originally Posted By: Mr Nice
I still have some SL rated Mobil 1.


I still have some SG rated Amoco Ultimate synthetic (only used in my OPE).
I still have some SH rated Pennzoil Performax.
I still have some SJ rated Exxon full synthetic.
I still have some SJ rated Quaker State full synthetic. (the original clear bottle).
I still have some SJ rated Havoline full synthetic.
I still have some SJ and SL rated Mobil 1.
I still have some SL rated Havoline full synthetic.
I still have some SL rated Havoline dino.


I have no problem using any of these except the SG stuff in my Corolla or Elantra because the Corolla specs SL and the Elantra actually allows SJ in the Owners Manual. I ran 2 OCIs of SH rated Performax in my Elantra and had a very good UOA. My oil is stored indoors and has never seen freezing weather.

 

[Jetronic]

Originally Posted By: kschachn
Originally Posted By: Jetronic
he's talking about gelation, where an oil is cooled very slowly and starts to "freeze over" at much higher temperatures than the regular pour point suggests. once heated, the oil becomes liquid again, but isn't it's old self yet.

Used oil can get this behaviour above 32°F, I've seen 60°F mentioned in severe cases. Engines have died over this before the mechanism was understood.


Is that the same as the cloud point? That was the test we ran in college, it may be the same.

But it's not a problem today correct? So all the warnings in this thread are no longer applicable? I can still start my old BMW at -25 F with the usual Castrol 0W-40 and not worry?


It's less of a problem, but not gone yet. I don't think it'll be ever gone as long as we use oils containing wax.

It's also not the cloud point, however, that is alo caused by the wax crystalising.

Castrol 0w-40 won't be an issue, it's a group IV oil.

Selby did a lot of work regarding this issue, I suggest if you're interested, you look it up.

http://www.machinerylubrication.com/Read/30329/engine-oil-quality

Quote:
This knowledge and bench test, which initially seemed to predict both forms of failure, were not enough. In the winter of 1979-80 in Sioux Falls, South Dakota, a cooling cycle showed that air-binding could occur under relatively mild cooling conditions. Over a 24-hour period, a number of engines containing oil were ruined. The cooling cycle had produced a condition in which the oil became air-bound. The costly incident revealed the need for a more sensitive bench test that would accurately predict the tendency of air-binding pumpability failures.



Quote:
The air-binding engine oil that caused the Sioux Falls failures provided a solid case study. A new bench test instrument and technique were developed to indicate any tendency of the test oil to gelate. The technique, which involved continuous low-speed operation of a cylindrical rotor in a loosely surrounding stator, was immediately incorporated into engine oil specifications and later became ASTM D5133. This not only showed the oil’s tendency to become flow-limited but also specified the degree of gelation that might occur over the measured temperature range (typically minus 5 to minus 40 degrees C). The parameter was called the gelation index. Today, engine oil specifications for multigrade oils require a maximum gelation index of 12. 




So ASTM now has a test for unused oils, used however is another matter

 

[Shannow]

kschachn,
the issues that Jetronic has linked to were a particular (not rare, but not common) mix of ambient temperature change profiles that caused the dissolved wax to start to form crystals, and like a slushy, not make it to the engine pick-up point.

That's when they dropped "pour point" and cranking and went to MRV (as suggested, Selby's papers are gold) and cranking. An oil that is tested for 0W is allowed to slip a grade to 5W in service and still pass. (Not mandatory obviously, but a part of it).

I know that you are chemistry background, and the PPDs are a bit like scale inhibitors, in that they inhibit "orderly" growth of crystals and thus make smaller irregular items that don't "gel".

There were (and a question that I've asked one of the formulators on the board, it's still possibility) that when mixing, these things don't play well together and give predictable "0W+0W=0W" results...different question.

Also, even synthetic oils may/can/will have additives that will do similarly, and behave like wax.

Now to the cold storage thing, I've read some stuff that prolonged storage of oils, even above their "freeze" point can establish gel like changes that won't reverse until about 80C...so an oil stored for months in a garage at sub freezing (how much and far is debatable) may not reflect it's "W" rating until the first thermal cycle.

University 101 appears to be wrong on that one...there's an effect, and it's reversible.

for giggles

http://www.instituteofmaterials.com/wp-c...n-Formation.pdf

 

[kschachn]

Thank you for the responses. To be honest I was being a bit sarcastic about the 60 degrees thing, but I see that I didn't totally understand what was going on. I kept coming back to the environment that the oil could see in shipping and storage, along with normal operational temperatures for many in the world. I'd never really looked into PPD but I assumed they inhibited the growth of something undesirable in the oil.

So maybe here in Wisconsin it would be advantageous to store oil indoors, especially during the winter.

 

[Nickdfresh]

I'd just save it for a lawnmower...

It probably won't hurt anything, but isn't what your current listed cars call for...

 

[RPMster]

It's fine to let an SL oil sit for years in temps below 0 F, as long as you remember to microwave it for 2 to 3 minutes per quart before using it. The microwaving will re-animate the elves out of their chilly dormancy, and then they'll get to work quickly to re-condition the oil's ingredients at the molecular level.

Or, you may skip the microwaving, but then you must only use the oil between the 1st full moon after the Vernal Equinox and Halloween.