Oil Compatibility Issues between brands?

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Found this post from Lake Speed Jr. from another forum:

Here is my take on this. There is simply not enough room on a label to write down everything somebody could possibly need to know about an oil. We have published an "instruction sheet" that is on our website (http://www.drivenracingoil.com/docs/...ng_Oil_351.pdf). It states that for best results, drain and flush the system. With all of that said, over the 15 plus seasons doing these oils for Joe Gibbs Racing, we have seen where some oils simply do not like other oils. Each oil in isolation is fine, but the combination of the two (even a 90% to 10% ratio) can cause a change in performance. This is a topic covered in the Society of Tribologists and Lubrication Engineers Certified Lubrication Specialist program.

In everyday life, when somebody experiences one of these occurrences, they think the oil they just installed must be poor, so they either switch back to the previous oil or go to a third option. In most cases, this resolves the "chemistry conflict", and the person moves forward. I've seen this happen first hand at least 3 times. We used to see this happen if a customer switched directly from Red Line racing oil to our XP racing oil. Strange things like increased blow-by, oil consumption, loss of power would happen. It even happened at JGR doing a series of oil tests and we had to flush the engine twice to get the baseline oil back to the baseline numbers. On the other hand, I've had people tell me they swapped from Red Line to our oil and never experienced this. I've also seen this happen between other brands of oil (not our products) and I've heard stories of different brands having "weird" interactions.

The point I am trying to make is this, odd things can happen when you mix different chemicals (motor oils and fuels) and put them in a chemical reactor (the engine). The vast majority of the time, nothing strange occurs, but every so often, something odd does occur.

I will say this, the more swapping between brands that you do, the more likely this is to happen. Also, the use of any oil and/or fuel additives compounds the likelihood of something strange occurring.

The best advice I can offer is to do regular oil analysis, and if you decide to change brands of oil, drain and flush the engine (the BR oils are great flush oils). Go half the normal distance, and then do an oil change. This helps clean and flush the system so that the oil can form and maintain the tribofilm that it is designed to do. At that point, you have a better reference for how that oil works for your engine, in your operating environment.

Thanks,
Lake Speed, Jr.
Certified Lubrication Specialist
Driven Racing Oil - Born From Joe Gibbs Racing, Driven To Win
13201 Reese Blvd, Suite 200
Huntersville, NC 28078
704-239-4401 cell
704-944-7538 fax


Lake is definitely more credentialed and experienced than me, so I'll defer to his experience (and authority).....but I personally have a hard time believing this to be a regular occurrence.

Thoughts?
 
Well I'm not surprized 1 bit. On watch collector forums, there are a plethora of posts such as " Can I dive with my new Rolex Submariner?"

As always, the statement needs qualification.
 
I think that the answer is (as usual) ... It Depends!

With many of today's commonly used off-the-shelf lubes, the formulations are very similar. Admittedly we cannot see some chemical compounds in a VOA, but as a generalization, between PDS and VOA data, we can get a reasonble picture of what's in the bottle. In "normal" O-T-S lubes, the amount of calcium, magnesium, boron, zinc derrivatives, phos, etc all varies to some degree, but generally they are similar. Not the same, but similar. And therefore mixing lube brands (or even product lines within brands) isn't inherrently dangerous and generally is safe. It may not be optimum, but it's generally safe to do so.

However, when you get into the weeds of boutique and super-premium brands (such as HPL and others), the chemistry is VERY specific, even within their own product lines. Even small changes in things like anti-foam additives (too much or too little) can affect the overall product performance. If you try to make a Franken-brew with these types of products, you do risk upsetting the very delicate balance that the blender has worked hard to achieve. Could it be catastrophic and destroy your engine? Probs not. But could it be deterimental? Most certainly it can be. It's not an assurance that it will be bad, but it certainly COULD BE bad. It could be as benign as just losing a few HP at 6k rpm, to badly aerating the lube, or something in between.

If always mixing common lubes were bad, we'd see thousands of dead engines every year; obviously this isn't the case. But there are stories of people going way off the reservation with very specialized products and things not ending well. Much of it depends on just how "boutique unique" you want to be.
 
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I think that the answer is (as usual) ... It Depends!

With many of today's commonly used off-the-shelf lubes, the formulations are very similar. Admittedly we cannot see some chemical compounds in a VOA, but as a generalization, between PDS and VOA data, we can get a reasonble picture of what's in the bottle. In "normal" O-T-S lubes, the amount of calcium, magnesium, boron, zinc derrivatives, phos, etc all varies to some degree, but generally they are similar. Not the same, but similar. And therefore mixing lube brands (or even product lines within brands) isn't inherrently dangerous and generally is safe. It may not be optimum, but it's generally safe to do so.

However, when you get into the weeds of boutique and super-premium brands (such as HPL and others), the chemistry is VERY specific, even within their own product lines. Even small changes in things like anti-foam additives (too much or too little) can affect the overall product performance. If you try to make a Franken-brew with these types of products, you do risk upsetting the very delicate balance that the blender has worked hard to achieve. Could it be catastrophic and destroy your engine? Probs not. But could it be deterimental? Most certainly it can be. It's not an assurance that it will be bad, but it certainly COULD BE bad. It could be as benign as just losing a few HP at 6k rpm, to badly aerating the lube, or something in between.

If always mixing common lubes were bad, we'd see thousands of dead engines every year; obviously this isn't the case. But there are stories of people going way off the reservation with very specialized products and things not ending well. Much of it depends on just how "boutique unique" you want to be.
In everyday life, when somebody experiences one of these occurrences, they think the oil they just installed must be poor, so they either switch back to the previous oil or go to a third option. In most cases, this resolves the "chemistry conflict", and the person moves forward. I've seen this happen first hand at least 3 times. We used to see this happen if a customer switched directly from Red Line racing oil to our XP racing oil. Strange things like increased blow-by, oil consumption, loss of power would happen. It even happened at JGR doing a series of oil tests and we had to flush the engine twice to get the baseline oil back to the baseline numbers. On the other hand, I've had people tell me they swapped from Red Line to our oil and never experienced this. I've also seen this happen between other brands of oil (not our products) and I've heard stories of different brands having "weird" interactions.

The point I am trying to make is this, odd things can happen when you mix different chemicals (motor oils and fuels) and put them in a chemical reactor (the engine). The vast majority of the time, nothing strange occurs, but every so often, something odd does occur.
I think jumping to the "pile of failed engines" is taking it a bridge too far ;) My takeaway from the part I quoted from the OP is that performance, when actually tested, can be significantly impacted. Average Joe isn't going to know this is happening and it's unlikely a UOA is going to show it, but if you were to run the mixed product through the sequences and standard tests you'd likely find that the performance has been reduced.

I know probably the most common "negative" interaction is a reduction of the Winter grade due to PPD dose no longer being appropriate for the base oil blend of the mix, but I'm sure there are others, such as FM balance, different VII types...etc.

And of course, as he noted, it's the same way with additives (of course some are far worse than others, ahem, Lucas, ahem). There's no way they've been tested with every possible chemistry, so there's no way to guarantee the increased performance claims, heck there's no way to even guarantee the performance of the final product won't be worse with the additive in play.

As I've noted repeatedly, oils are fully formulated products and their performance has been qualified through myriad performance tests to claim both the API approval and numerous OEM approvals. @buster touched on this with his recent Mobil racing thread and @kschachn likes to draw attention to the importance of OEM approvals and testing regimens. Some oils are taken beyond even that with this as a baseline, from which additional formulation tweaks and testing are performed to optimize the product further. Ergo, it's breathtakingly naive for people to think that by dumping one specific substance into this balanced formula, that they are going to make it better.

And yes, you are quite right that many off-the-shelf lubes are formulated similarly, but that's mostly the result of there only really being a few major blenders. Shell/Pennzoil/Quaker State are going to be similarly blended but they are likely different from Mobil, who is in turn different from Castrol, and we've seen differences in FM selection between these as well. Now of course you have Amazon Basics/SuperTech/*insert other store brand* Warren products too, which are all probably the same or at least incredibly similar, using a cookie cutter additive package.

With HPL/Amsoil/Redline/Gibbs/RLI...etc yeah, you get into that "beyond the baseline" territory where the product is even more finely tuned and I suspect this makes the odds of the chemistry being more sensitive to interaction much higher.
 
However, when you get into the weeds of boutique and super-premium brands (such as HPL and others), the chemistry is VERY specific, even within their own product lines. Even small changes in things like anti-foam additives (too much or too little) can affect the overall product performance. If you try to make a Franken-brew with these types of products, you do risk upsetting the very delicate balance that the blender has worked hard to achieve.
With HPL/Amsoil/Redline/Gibbs/RLI...etc yeah, you get into that "beyond the baseline" territory where the product is even more finely tuned and I suspect this makes the odds of the chemistry being more sensitive to interaction much higher.
ASTM D6912 exists to ensure homogeneity, miscibility and prevention of catastrophic failure - but there has never been any guarantee that performance of the final mixture will not be diminished. I guess with boutique oils where full compliance with industry norms can be questionable, the potential for "performance issues" can be even greater...
 
ASTM D6912 exists to ensure homogeneity, miscibility and prevention of catastrophic failure - but there has never been any guarantee that performance of the final mixture will not be diminished. I guess with boutique oils where full compliance with industry norms can be questionable, the potential for "performance issues" can be even greater...
Yup, exactly, as @Shannow used to say, the standard just ensures that they won't split like mayonnaise, it in no way guarantees maintaining the performance associated with any of the approvals either product carries on their own.
 
GREAT info for sure as MANY of us average people actually know LESS than they THINK they know!!
 
Joe Gibbs Racing. Those are the guys that run a small block V8 at redline for a few hours around a 2.66 mile oval? Yeah, they probably are fairly picky about their oil. Out here on the street, I personally believe the circumstances don't warrant being so picky. Mixing is fine.
 
“Additive clash” used to be something that was talked about. Additive solubility was also something that has been a concern and noted over time.

How much of those is real? New? Unique to modern formulations? Hard to say. Therein lies the best practice. That is, limit what opportunity exists for such issues by sustaining as consistent a chemistry as is viable. That isnt rocket science.

The experimental design and analytical work to validate true compatibility is massive, and not a cost that anyone wants to bear. Just because companies have fancy labs doesn’t mean they can speculate and identify all long term outcomes from all mixing and comparability scenarios. Most will not be the case. Much of the chemical systems used are compatible, miscible, etc. some may not be. Even if they aren’t, the issue may not present. Remember, we can’t really discern the differences in longevity across a fleet, between super boutique oils and OTC oils. There’s too much variability. A tiny fractional mixture? Even less resolution. But we have a general idea what can happen, and what best practices may avoid it.

In my case, for our Honda cars where I may not change the filter every time, I make an effort to keep the same oil formulation for both OCIs. This way even if the first is “underperforming” (whatever that means for the oil mix at hand), the second shouldn’t.
 
I’ve been giving my blazer an oil cocktail for the last few years. Anything left over goes to the truck.

It’s only filled with 0w40 now because I felt like trying it. It has 5 quarts of whatever w 35ish for the next run.
 
Don't forget the oil stabilizer! :ROFLMAO:




Don't need any of that if you just dump some of this in there!!!!!

ELPSL11000-Engine-Treatment-12-oz_Straight-1500x1500-@-96-dpi-160x300.jpg


For anyone that doesn't remember the 90s and has 30 minutes to waste, here you go. Or just watch the first 60 seconds and don't die laughing.

 
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