Who uses Pennzoil Platinum full synthetic?

You're very close to the story. Pennzoil at one time advertised their oil as being made from paraffinic base stocks, which is an another name for alkane hydrocarbons. Paraffinic hydrocarbons can range from gases, to liquids, to solids at room temperature.

However, Billy Bob read the advertisement and exclaimed "Paraffin! Gadzooks! That's the stuff Erma uses to seal her jelly jars!"

This really got a lot of traction as multi-viscosity oils became prominent as most oils of that era has significant sludging issues. The average consumer found out his engine was sludged up and decided "Well it's no wonder, that **** Pennzoil has paraffin in it!".

Pennzoil never had paraffin waxes in the oil. And they never had more sludge issues than the other oils of the era. They were however one of the most popular brands at the time so if you had an engine with sludging issues there was a fair chance it was running Pennzoil. It was a case where someone took a small bit of information and ran with it beyond their understanding.
What does the cloud point of oil show?
 
None? So there is no cloud point at all?
Here is an old question asked about Pennzoil cloud point.
1974 article in Popular Science.
Limits are set by the test. Does not mean change does not happen, just does not reach the limit set. The wax can clog oil filters.
 
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Yes, I used to run cloud point tests in college. I was asking about the GTL-derived product where you said there was no wax.
Not absolute… My bad. Since I got a knowledgable person here, at what temperature could you go to check cloud point in relation to the pour point?
 
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I mostly used 0w-20 in my truck with 255k with no issues. I occasionally used M1 too.
 
Not absolute… My bad. Since I got a knowledgable person here, at what temperature could you go to check cloud point in relation to the pour point?
I don't know what you're asking there. Besides, I was only asking about your statement in regards to wax and GTL. Neither one is very important these days in terms of oil performance as related to engine operation at low temperatures. There are better predictors now. If you use an oil with a winter rating that is appropriate for your expected starting temperatures then wax will not clog the filter.
 
I don't know what you're asking there. Besides, I was only asking about your statement in regards to wax and GTL. Neither one is very important these days in terms of oil performance as related to engine operation.
Just asking how far the temperature of the cloud point test needs to go.
 
Just asking how far the temperature of the cloud point test needs to go.
Needs to go for what? It's the measured variable so it is what it is determined to be. I don't know of an approval or license that has a stated limit, like I said it's not a very good predictor of performance. Much like flash point it is subjective and has a high reproducibility and repeatability tolerance, and is also dependent on test methodology.
 
I had to look it up but the lowest temperature to test lubricating oils for cloud point is about -80C. We used dry ice in acetone IIRC.

It's more important for diesel fuel since that has a much higher cloud point and can definitely clog fuel filters.
 
I had to look it up but the lowest temperature to test lubricating oils for cloud point is about -80C. We used dry ice in acetone IIRC.

It's more important for diesel fuel since that has a much higher cloud point and can definitely clog fuel filters.
Diesel has a cloud point 20-35 degrees F above the diesel pour point. Thanks for your input.

Just curious about lubricating oil?
 
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What does the cloud point of oil show?

I have no idea what the cloud point was of oils of the 60s and 70s, but I think I can say pretty confidently that they were quite a bit higher than the oils of today.

But, when people were connecting paraffinic base stocks with the sludging issues of oils of that era, I don't believe it was a low temperature operation issue. It was typically something that was discovered when you pulled a valve cover or oil pan and saw sludge deposits.

My guess is that this was attributable to the significantly less refined base oils and the VIIs in use in that era. But that's just a guess. I remember people talking about Pennzoil "having paraffin in it" and that being the reason there was so much goo in your valve cover, but I was just a teenager at the time and didn't understand the underlying issues. It was definitely something I heard from mechanics that had torn into engines and found sludge "at room temperate" or at least "at shop temperature" which in my area was never that cold. So I don't think there was much of a relation between cloud point and sludging problems.
 
I've used mostly Pennzoil Platinum 5W-20 through the past 60k miles, plus one change (by dealer) of TGMO, one change of Pennzoil Platinum 0W-20, and one of about two-thirds Pennzoil Platinum 5W-20 mixed with one-third Quaker State 5W-20. No apparent hint of oil-related issues with any of those.
 
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