Wear vs Vehicle Total Mileage

[BaBaFlyingSheep]

Does anyone know of any articles or data that tracks the amount of iron wear throughout the life of the vehicle?

I was only able to find this one graph, where they tracked the iron wear. Basically, what they're suggesting is that after the break-in period, the engine reaches a "prime" in terms of wear around 50k miles.

Then increases metal wear, and decreases again?

I assume that at some point down the line (maybe 250k+ miles?), there's been so much metal removed from the engine, that the oil just can't protect the gaps between moving parts (cylinder walls), and the iron wear will increase drastically.

I couldn't find any related threads on bitog (and I can't post on them yet).

Anyone have any thoughts on this, graphs, tracking their uoa's?

[mav1178]

I have never bothered plotting my data but you can do it if you want.

http://www.ft86club.com/forums/showthread.php?t=39983

My last 6 UOA had iron levels of 14 8 14 14 11 14

But I hope you realize iron wear in our engines is not as important as some other metals.

[Mr.ac]

? Our blocks are made of aluminum.
But yeah I get the interest. Pretty much heat is the enemy. Keep the heat down you'll have a car that would last well into the 300k mile range. Eventually something gives.

[Nickosport]

Originally Posted by Mr.ac

? Our blocks are made of aluminum.
But yeah I get the interest. Pretty much heat is the enemy. Keep the heat down you'll have a car that would last well into the 300k mile range. Eventually something gives.

Iron in oil doesn't always come from the block. Piston rings, bearing liners, cylinder sleeves are all iron. A lot UOAs can even tell you where the iron in the oil came from, whether its the rigs or cylinder walls or what have you. Some engines have aluminum cylinders coated with Nikasil, but the FA20 is an aluminum block with iron sleeves.

[Mr.ac]

Ah right on.

[bluesubie]

BITOG - Why iron ppm numbers are not good wear indicators.

And good info regarding uoa's in general.

...it is easy to assume that by carrying out a UOA you will be able to determine how quickly the engine is wearing out. As well, if you change lubricant Brands you will be able to compare the wear metal uptake results and then make a balanced best lubricant choice to make your engine last longer.

Sadly that logic is seriously flawed.

Single pass (random) UOAs will provide some information regarding wear metals but unless you have a history of your engine’s performance up to around 1 million miles the results are simply that – UOA results! As an example a limit of 150ppm of Iron is a reality – after say 100k it means the lubricant should be changed and all is well. But what is the situation if you have 150ppm of Iron at 5k? Where would you look what would or could you do? So UOAs are really a diagnostic tool – one of many!

The other parts of the UOA Report will be much more valuable to you – it will tell you about the CONDITION of the lubricant and its suitability for further use. This will enable you to get the maximum safe use from the lubricant saving a valuable resource in the process.

http://bobistheoilguy.com/used-oil-analysis/

Originally Posted by BaBaFlyingSheep

I assume that at some point down the line (maybe 250k+ miles?), there's been so much metal removed from the engine, that the oil just can't protect the gaps between moving parts (cylinder walls), and the iron wear will increase drastically.

I don't think this is the case. I've never heard of wear becoming so bad that the oil cannot protect the gaps between moving parts. I recall a trend of uoa's on nasioc several years ago on a high mileage WRX. Lead jumped up quite a bit and it was speculated that a bearing was going out. OTOH, I've seen uoa's on cars with 250,000 miles and uoa wear was lower than similar cars with only 50,000 miles.

[BaBaFlyingSheep]

Originally Posted by bluesubie

BITOG - Why iron ppm numbers are not good wear indicators.

I don't think this is the case. I've never heard of wear becoming so bad that the oil cannot protect the gaps between moving parts. I recall a trend of uoa's on nasioc several years ago on a high mileage WRX. Lead jumped up quite a bit and it was speculated that a bearing was going out. OTOH, I've seen uoa's on cars with 250,000 miles and uoa wear was lower than similar cars with only 50,000 miles.

I know that iron is one of the few wear materials that goes up linearly with the miles of the oil, but the increased iron wear is kind of like what Nickosport was saying, there are a lot of parts that contain iron.

The concept is basically gaps become so large that you get increased vibration and metal-to-metal contact, this can happen anywhere. Vibration also increases heat, especially at the speeds that engines are running at. This combination basically thins out your oil film, and therefore, reducing protection.

All-in-all, I'm just trying to debunk some oil myths and look for a potential oil brand to go with. A lot of people say you can't mix brands because of the additive packages, which true, but all oils need to abide by some sort of standard, and I'm beginning to think perhaps oils aren't that different.

The problem is, a lot of my data was during the break-in period, so technically can't do an apples-to-apples comparison until I get more data. Hence wondering if there was a correlation between engine life and amount of wear material.

Take a look at my oil analysis of different brands and even mixes. Did not find anything out of the ordinary. M1 EP, Kendall GT-1, RP. I plan on trying out M1 AFE and Pennzoil Plat, and probably RL and Motul later down the line. I guess the only thing that was a bit strange was the GT-1, where my oil consumption went higher than the other brands. I'm hoping the liquid Ti is worth the Ti-plating and saving my cat. Molecule from bitog also couldn't find any conclusive answers on Ti vs Moly-plating, but I'm pretty sure I'm done with GT-1 after I finish the rest of my inventory.

I'm probably going to keep track of all my oil analysis, even after the 60k mile warranty, and maybe I'll be able to get some real hard data. I have a heavy foot and drive pretty consistently since this is my daily. Maybe plot in a graph by material?

[bluesubie]

Originally Posted by BaBaFlyingSheep

Molecule from bitog also couldn't find any conclusive answers on Ti vs Moly-plating, but I'm pretty sure I'm done with GT-1 after I finish the rest of my inventory.

Molakule has also changed his tune a bit about moly. He said that there's industry info stating that moly isn't being thought of as an anti-wear additive any longer. Only as a friction modifier. This wasn't in the White Papers section, but in a reply to a post IIRC.

Originally Posted by BaBaFlyingSheep

I'm probably going to keep track of all my oil analysis, even after the 60k mile warranty, and maybe I'll be able to get some real hard data. I have a heavy foot and drive pretty consistently since this is my daily. Maybe plot in a graph by material?

I would have gone with Oil Analyzers Inc if you're getting this deep into it. For a cheaper price you get TBN, oxidation, nitration, and sometimes fuel reading by gas chromatography instead of the estimate that Blackstone does. Better yet, hire your own tribologist for the best feedback to your wear questions.
http://www.dysonanalysis.com/

In the article that I linked above by Doug Hillary, he cautions about reading too much into these cheap uoa's and using them as a tool to try to compare uoa wear with actual engine wear (teardowns and measurements are the best way to do that).

Here are some graphs that Terry Dyson did for an STLE conference when he was working with RS4 owners and Renewable Lubricants Inc. to develop an oil that performed better than VW502 oils. http://renewablelube.com/files/8514/...ngine_Oils.pdf
Unfortunately, no high mileage stuff there.

Doug Hillary would probably be able to answer your questions, although he doesn't post very much at bitog these days. Terry Dyson can answer your questions, although it will cost you.

I pretty much gave up on uoa's after doing them religiously for about twelve years. As Doug Hillary said, they're better to determine the condition of the lubricant (or maybe to alert you of an obvious problem), but they're not always useful for predicting impending failure. I blew a turbo with good uoa's. Don't think too hard about this. You'll hurt your brain.