I am currently using Mobil 1 5w30 during winter and Pennzoil multigrade 5w30 summers. Will this cause any longrange problems?
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- Thread starter pepper32
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Pepper, maybe you ought to think about going to 0W-40 or so in Fairbanks. I lived up there for 20 years before coming to SoCal to thaw out, and never made it back. Fairbanks in the winter is my idea of hell, although Barrow has it beat.
Mike
Mike
Patman
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The only way it would cause a problem is if you're doing extended oil change intervals. With extended intervals you want to run the same oil.
I would also have said go to the 0W40, but it doesn't look like that'll buy you much.
Borderline pumpability for the pennzoil 5W30 is -31*f, M1 5W30 is much better at -51*f. But M1 0W40 is only 2 lower at -53*f. The 0W40 pour point is 11* lower but that doesn't seem to help mechanically. M1 0W30 is down at -58*f, which might be my choice.
(I'm getting M1 data from online specs updated 10/02.)
David
Borderline pumpability for the pennzoil 5W30 is -31*f, M1 5W30 is much better at -51*f. But M1 0W40 is only 2 lower at -53*f. The 0W40 pour point is 11* lower but that doesn't seem to help mechanically. M1 0W30 is down at -58*f, which might be my choice.
(I'm getting M1 data from online specs updated 10/02.)
David
Patman
Staff member
Yes, typically the borderline pumping temperature is about 20 degrees F higher than the pour point. So if the pour point of an oil is listed at -60F, your safe point for running this oil is -40F and higher. Below that you run the risk of the oil not pumping properly.
So just because an oil's pour point is listed at a certain temperature doesn't mean that's the safest temperature to take it to.
Same here. Really, I'd stick with one or the other. The Pennzoil would be okay most years.
FWIW, Weather.com says temps haven't been below -31*f in Fairbanks since '93 when it hit -58*f. I'm curious, does that sound accurate? Here's the link:
http://www.weather.com/weather/climatology/monthly/USAK0083
David
FWIW, Weather.com says temps haven't been below -31*f in Fairbanks since '93 when it hit -58*f. I'm curious, does that sound accurate? Here's the link:
http://www.weather.com/weather/climatology/monthly/USAK0083
David
I've read that pumpability limit is roughtly 10F above it's pour point since 'pour point' is determined by no movement of the oil when placed on a vertical surface for 10 seconds....so about 10 degrees F above this, the oil should be able to be pumped through the engine. M-1 lists pumpability limits for all it's oils...eg. 15-50 pours at -45F, pumps at -35F.
Dr. T, The safe guideline I've read is 20 degrees. No specs I've seen have exceeded that, but they're usually between 10 and 20 degrees apart, a few much less. M1 15W50 pour point is -49*f (-45*c) and borderline pumpability is -35*f.
David
[ December 12, 2002, 11:44 AM: Message edited by: OneQuartLow ]
David
[ December 12, 2002, 11:44 AM: Message edited by: OneQuartLow ]
I would still recommend considering them and would not call them "meaningless". The cold crank test actually provides a precise measurement. The pour point only offers the point at which an oil barely flows out of a test tube. The pumpability limits being offered above are guessimates at best.
Johnny had an explanation for Pennzoil's confusing cold temp specs that makes the oil look worse than it is.
I think the CCS and MRV tests are the best way to compare the low temp performance of an oil. The caveat is that most companies only post the CCS spec and the spec is often out-of-date. This creates a lot of confusion because the newer J300 limits are 5*C colder than the old. Pennzoil vs Mobil 1 is a perfect example. Pennzoil's 5w specs are listed 5*C warmer than Mobil 1's 5w specs because Mobil 1 has updated their specs and Pennzoil hasn't.
[ December 12, 2002, 07:31 PM: Message edited by: Jay ]
Thanks for all the input guys. I use conventional oil in the summer because it's cheaper. I have four vehicles and only drive about 4000 to 5000 miles per vehicle in a year. Because of the cold and frequent short trips ( four miles to job), I change the oil every 3 months. BTW the Mobil 1 5w30 performs very well in Fairbanks.
Another set of numbers to consider are those values of cP (or centipoise) on your respective product's data sheets. The SAE has a spec called J300 (Standard J300: Engine Oil Viscosity Classification*HS-23/00*). This spec is translated as requiring "a maximum starting viscosity of 3500-4500 centipoise (cP) at the appropriate low temperatures". You can refer to this link as an example:
http://www.savantgroup.com/newslett/savant/jan96/jan96b.htm
You might look at the data sheets for the products you're considering and see if they meet this criteria. Most are listed in degrees C and many have the "cold cranking" (vs. "cold pumping") designation so for those of us still in the Dark Ages:
-15C = 5F
-25C = -13F
-30C = -22F
-35C = -31F
For example, Pennzoil Multigrade Motor Oil 5W-30 has a value of
Hope this helps you with your descision. It's a little bit more precise than the pour point.
http://www.savantgroup.com/newslett/savant/jan96/jan96b.htm
You might look at the data sheets for the products you're considering and see if they meet this criteria. Most are listed in degrees C and many have the "cold cranking" (vs. "cold pumping") designation so for those of us still in the Dark Ages:
-15C = 5F
-25C = -13F
-30C = -22F
-35C = -31F
For example, Pennzoil Multigrade Motor Oil 5W-30 has a value of
Hope this helps you with your descision. It's a little bit more precise than the pour point.
These numbers are essentially meaningless. Know why? Because the J-300 spec for a 5wXX oils says the the CCV must be <6600 at -30*C. All Pennzoil is telling you is that the oil meets the spec. What it is NOT telling you is the actual CCV of the oil. I've noticed this sort of practice on all the Pennzoil and Quaker State spec sheets.
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