Does older oil protect better?

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I've read here, in various guises, that older oil, oil that's been used in the engine for some time (specific time has never been made clear) affords better protection than fresh oil. I wonder if there's any truth to that?

I recall it being said in one thread that it's a good idea to leave a small amount of the used oil in the engine when doing a change, as it would "season" the new, fresh oil, and better protect the engine. Given that there's often oil left in the engine when doing a change, there's often old oil mixed with the new. For example, 1.8 quarts remains in my engine when doing a complete change.

So, what's the story about using aged oil for greater protection?
 
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If you read that then did you read the rest of the thread? The singular source of that information based the conclusion on some very specific circumstances that did not correlate to actual operation. Find the threads and read the rest of the story especially from poster Shannow.

The bottom line was that it was a flawed study which came to flawed conclusions.
 

Shel_B

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I only had a vague recollection of the discussion, and only the comment about about using older oil stuck with me. I'll see if I can locate the thread. Tks!
 
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You always leave a (not so) small amount of used oil in the engine. Engines are difficult to be drained completely.
For example on my Golf GTI total capacity is 6,6 l, while you change only 5,7 l including filter. So almost one quart/
Liter will remain within the engine. It's similar on my Mini Cooper. My Porsche is a different story due to dry sump.
 

ZeeOSix

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GF-6 is suppose to protect cam-chains better than GF-5 (and I'd assume all previous GF ratings). Cam chains are mixed and/or boundry lubrication, so GF-6 may also add wear protection to other components in the same lubrication realm. There was a spider chart posted in other threads showing key performance points of GF-6 vs GF-5.
 
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Some memes (Old sense of the word)repeated here

old oil can be dirtier than oil that has been circulated.

oil with 200 hours lhas better lubricating properties.

boundary lubrication of new Fresh oil is not as good as oil that has been in service.

things change for the oil during service. Some properties get better while others slowly degrade overtime. i think The majority of an OCI the oil is at its best, once it is “broken in through some heat and friction) and it remains pretty **** good until it becomes depleted, climbs or falls out of desireable,viscosity, can’t fight acids, and or carries to many abrasive particles and the suspension package gives up and deposits start to accumulate.
Short OCIs are a hedge against the latter problem while optimized OCIs spend as much time in the sweet deliverable zone we want a lubricant to perform in before it goes from protection to a liability.
 
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GF-6 is suppose to protect cam-chains better than GF-5 (and I'd assume all previous GF ratings). Cam chains are mixed and/or boundry lubrication, so GF-6 may also add wear protection to other components in the same lubrication realm. There was a spider chart posted in other threads showing key performance points of GF-6 vs GF-5.

I typically don't pay attention to GF stuff but now that you mentioned, I recently bought some oil and it says GF-6A. what's the A for? I think I may have paid extra $ or 2 for the letter A. lol
 

ZeeOSix

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I typically don't pay attention to GF stuff but now that you mentioned, I recently bought some oil and it says GF-6A. what's the A for? I think I may have paid extra $ or 2 for the letter A. lol
A is put on everything but the 0W-16 viscosity, which gets B. Just a way of marking to help prevent someone using 0W-16 in a vehicle specifying a higher viscosity.

 
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