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Rotella: The world's first ever combined hair oil, foot ointment, and salad dressing

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Old Sep 9, 2015 | 06:34 AM
  #571  
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Originally Posted by '90Cherokee
The most widely accepted break-in that I've seen repeatedly endorsed is to run the engine though a range of power and RPM and not baby it or run a constant power or RPM for extended periods. I've seen evidence of this working very well.
And not running any 'break in' oil or zinc additive or 'break in' additive. That is like 'liquid sand' being added to your oil.
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Old Sep 9, 2015 | 07:28 AM
  #572  
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Originally Posted by '90Cherokee
Your hardening explanation doesn't sound right either. Some metals will work harden but I don't think any of those are used in wear areas of engines. Most materials that can be work hardened will also heat soften; brass, stainless, plastics, etc. Some cams are nitrided to resist wear which is a heat and chemical treating process that can't reliably happen in a running engine.
Okay, then why are zinc and phosphorous included in oil at all? Having them in the oil where they can find their way into exhaust reduces the life of the catalytic converter, which is why their levels were reduced in the SAE standards. Why not just remove them altogether if they don't have any beneficial effect in the engine? Are they just there to make the oil taste better on salads?

Originally Posted by '90Cherokee
The most widely accepted break-in that I've seen repeatedly endorsed is to run the engine though a range of power and RPM and not baby it or run a constant power or RPM for extended periods. I've seen evidence of this working very well.
Originally Posted by CobraMarty
And not running any 'break in' oil or zinc additive or 'break in' additive. That is like 'liquid sand' being added to your oil.
Here's what I know:

I have a Golen stroker. I had it broken in by Golen on the engine dyno. The engine dyno routine ran it through a range of RPM. The break-in instructions for the first 1000 miles said to continue subjecting it to a variety of RPM and loads, not to use cruise control, and not to baby it.

Golen also used break-in oil, Joe Gibbs Driven to be specific. It is a high ZDDP oil. Huh.

This engine has a 100,000 mile warranty. Golen requires the use of high ZDDP oil or a ZDDP additive to maintain that warranty. I use the Driven street rod oil (NOT break-in oil). Chad Golen told me on the phone that in all the time they have been selling the 4.6L stroker, they have only had one returned under warranty. Huh.

So if high ZDDP is "like 'liquid sand' being added to your oil," how is Golen able to have so many 4.6Ls on the road?

On one side I have reputable engine builders and oil companies explaining that higher ZDDP is necessary for strokers and aggressive cams to help harden the surfaces and prevent wear. On the other side I have some internet "experts" questioning that without providing any plausible motivation the establishment might have for lying to us about zinc. Guess who I'm more inclined to believe.
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Old Sep 9, 2015 | 08:16 AM
  #573  
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Fun thing about the metallic antiwear additives in engine oil - they are mostly temporary. ZDDP & moly both work as the engine runs to form a layer on friction surfaces. I wouldn't call this "hardening" in the same sense as, say, heat treatment, but more like buffering (albeit a really hard buffer).

The protective layer can, and does, get worn away by friction, as well as being attacked by the detergent additives in the oil. This is one of the reasons playing backyard chemist is not smart, but also the big reason why you shouldn't change your engine oil TOO often.

One of the links I posted way back on the first page I believe shows a lifecycle of a given OCI. Within the first thousand miles wear goes UP, then stabilizes as the additives basically settle in.

(Or so I recall, it might not even be in that list. I'm lazy lol. It was on a VW forum if I remember correctly)

Originally Posted by extrashaky
Are they just there to make the oil taste better on salads?
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Old Sep 10, 2015 | 11:29 AM
  #574  
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Break-in oil is not liquid sand at all. It's often devoid of detergents as they're not needed and a non-detergent oil has lubricating advantages. It also often has extra zinc and other additives that are advantageous during break-in that aren't really needed normally. Zinc crates a sacrificial layer, not hardening. A stroker presents no appreciable change in lubrication needs. Valve spring tension and cam profile can have a big impact and many people use valve springs that are much harder than actually needed. They sacrifice efficiency to have an extra bit of insurance against valve float. As for the Driven oil, they advertise "more zinc than normal oil" but don't publish numbers that I can find. They also tout some secondary cam protection stuff, something all oils have and even more so in low zinc oils. I'm not saying their oil isn't good, but they've provided no evidence that it's superior.

Other than the new filter, higher wear after an oil change doesn't make sense unless one is switching oil types between oils that have incompatible additive packages. If the old and new oils are the same it seems the new oil should just continue to do what the old was doing. If you have a scientific explanation for the increased wear I'd love to understand this. A new filter passes more junk than a used one so there could be some extra wear from contaminants. Some manufacturers used to, and maybe still do, recommend the filter change every other oil change.
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Old Sep 10, 2015 | 02:47 PM
  #575  
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The reason wear jumps at the beginning of a new oil load is the detergents are new and more aggressive..they attack the zinc boron and phosphorus anti wear buffer. Note this is a very small swing or jump and likely only could be seen by sampling oil in very short intervals across the oil life.
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Old Sep 10, 2015 | 03:02 PM
  #576  
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Yeah that's what I just said lol
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Old Sep 10, 2015 | 10:05 PM
  #577  
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Yeah problem is these guys don't get it... I have been prepping to teach this year's students about oil. I must say I have gotten some good examples of old wives tales and pure fabrication from this thread.. Along with a bunch of great data...
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Old Sep 11, 2015 | 10:09 AM
  #578  
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Originally Posted by '90Cherokee
Zinc crates a sacrificial layer, not hardening.
You are correct, and I was wrong. I misread an article about how zinc works in which the author stated that the zinc lays down a very hard layer, which it is. It's just not correct to characterize it as hardening the steel. Thanks for the correction.

Originally Posted by '90Cherokee
As for the Driven oil, they advertise "more zinc than normal oil" but don't publish numbers that I can find. They also tout some secondary cam protection stuff, something all oils have and even more so in low zinc oils. I'm not saying their oil isn't good, but they've provided no evidence that it's superior.
It consistently tests above 1200 ppm zinc in all the oil comparisons.
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Old Sep 11, 2015 | 04:56 PM
  #579  
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So the Zinc protective hard layer that is laid down is over time and doesn't happen in the first 20-30 minutes?


If it is laid down, why is there still so much zinc leftover in oil analysis after 3-4000 mile oil change?
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Old Sep 11, 2015 | 05:12 PM
  #580  
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Originally Posted by CobraMarty
So the Zinc protective hard layer that is laid down is over time and doesn't happen in the first 20-30 minutes?


If it is laid down, why is there still so much zinc leftover in oil analysis after 3-4000 mile oil change?
The oil was probably changed before it was necessary.
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Old Sep 11, 2015 | 05:24 PM
  #581  
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Yup changing oil too often is just as bad as changing it at too long of intervals.
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Old Sep 11, 2015 | 05:36 PM
  #582  
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Originally Posted by autosurgeon
Yup changing oil too often is just as bad as changing it at too long of intervals.
Exactly I'm at 6500 miles on delo 400 with a longer filter and going change and analyze at 7500 just to see how it's doing and probably go longer after that.
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Old Sep 11, 2015 | 05:58 PM
  #583  
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I hate to ask this, because I should really know already, what's the link or name of that trusted oil analysis place. Wanna see for my Jeep and Altima
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Old Sep 11, 2015 | 06:15 PM
  #584  
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Default Rotella: The world's first ever combined hair oil, foot ointment, and salad dressing

Originally Posted by sycoglitch
I hate to ask this, because I should really know already, what's the link or name of that trusted oil analysis place. Wanna see for my Jeep and Altima
Blackstone labs. I use chevron fleet services though.
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Old Sep 11, 2015 | 08:53 PM
  #585  
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Yeah Blackstone. First page dude lol. If you're near any truck joints or Caterpillar/Battlefield shops they also tend to do analyses.
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