98 Corvette, PP 5w30, 5800 miles

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Patman

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Here are the latest oil analysis results from my 98 Corvette



Analysis by Wearcheck Canada


5800 miles on oil
Nov 14 to July 18 (8 months)
106,000 miles on the car
Pennzoil Platinum 5w30
NAPA Nascar oil filter
Vararam cold air kit (with a cotton gauze filter)
LS1 5.7L V8 engine
7 qt oil capacity
1.5 qts of makeup oil added
Oil life monitor was at 12%



Iron 18
Lead 3
Aluminum 12
Copper 1
Chromium 2
Tin 1
Silver 0
Titanium 0
Nickel 0

Silicon 11
Potassium 0
Sodium 0
Boron 38
Barium 0
Vanadium 0
Manganese 1
Sulfur 2301
Calcium 3257
Magnesium 19
Moly 57
Phosphorus 763
Zinc 909


Oxidation 69
Nitration 53
Sulfation 57
*note, the above three values are not percentages*



ZDDP 17.5



Viscosity at 40c 58.7
Viscosity at 100c 10.9
Viscosity Index 180


I changed the oil earlier than I had planned (I always wait for the oil life monitor to hit zero) because my Fram Sure Drain plug system was starting to leak oil and messing up my garage floor. Luckily I had a spare new one to replace it.

I refilled the crankcase with Pennzoil Platinum 5w30 again, but this time I am using the Fram Extended Guard oil filter.
 
I don't like that aluminum amount at all. It's very, very high for less than 6k miles.

Usually, I'd expect to see high silicon explain it, but that's not the case here.

The rest is great, but it looks like something is causing bad piston wear in your engine.....
 
Nice one, Pat. How'd you get that UOA so fast?


Originally Posted By: Johnny
Your Vette does well on this oil Patman. You realize the FRAM hammers are getting ready to hit you.


Let em. The Extended Guard is a good filter and they'll just be showing their ignorance.
 
Originally Posted By: Johnny
Your Vette does well on this oil Patman. You realize the FRAM hammers are getting ready to hit you.


Yep, I know that I'm going to get flack on this one, and I am still a big hater of the Fram orange can, but the extended guard one is really good and it's a great deal up here compared to the other premium filters.
 
Originally Posted By: addyguy
I don't like that aluminum amount at all. It's very, very high for less than 6k miles.

Usually, I'd expect to see high silicon explain it, but that's not the case here.

The rest is great, but it looks like something is causing bad piston wear in your engine.....


I wouldn't be so quick to push the panic button just yet. I will say that aluminum did go up from the previous run. In a 7k run it was 7ppm. So there is an increase, but I'll wait for the next run to see how it goes from there.
 
In my initial auto-rx results thread, I have a pic of a cut open and stretched out Extended Guard. The media is very robust. I'd link to the pic but am presently blocked from photobucket.
 
Originally Posted By: BrianWC
Nice one, Pat. How'd you get that UOA so fast?




I dropped my sample off directly at the lab on Monday morning. I was a bit disappointed that I didn't get the results sooner actually. They finished up every single one of the tests by Monday afternoon, except for TBN, and then my sample sat there waiting for the TBN test for the entire day yesterday. They finished it by the end of the day but went home before adding their comments and releasing the results to me. (I find out all this information online as that's how I get my results, through Wearcheck's online service which shows you step by step what tests are being done on your samples at any given moment)

What is annoying is that TBN test they do is a new one they've added that only costs $1 instead of $10 but it's not as accurate (which is why it's only $1) I don't even post that TBN because it's not directly comparable to the true TBN tests that they do for $10 (for instance, they told me the TBN on this sample was 8.6, and I know from previous UOAs where I got the higher cost TBN test that it would've been closer to 3 or 4) This was my last sample kit so when I buy more I will just get the most basic package without TBN, and my UOAs will be processed much quicker in the future.
 
I added more info to my original post, as there is another section on Wearcheck's site which gives additional info, such as ZDDP level of 17.5 (have no idea what this means), Manganese, Vanadium, Oxidation, Nitration, Sulfation, and Sulfur level. I also corrected the VI to 180, their original data said 172, but that was their error, that was the VI from the previous UOA.
 
I'd start to worry, if it were me.

UA for Al is usually somewhere around 3-4ppm; not usually more than 5ppm for 'most' engines.

At 7 it is high; and if it is now moving up to 12 with less miles (and less hard racing)....something is wrong, and its not abrasive dirt.
 
Well hopefully the aluminum number was just a one time occurrence and it won't happen on the next one. The engine is running fantastic right now, there is no indication of any trouble (sounds normal, runs nice and smooth, MPG hasn't gone down, etc)
 
Originally Posted By: hate2work

I wonder how much higher the Al reading would have been if you hadn't added 48 oz of make up oil?



Probably not much different if you take into account the large size of my crankcase. Adding 1.5 quarts of makeup oil to a 7 quart system isn't going to skew the numbers as much as adding 1.5 quarts to a 4 quart system would. At the same time, one could argue that such a large 7 quart system dilutes the wear metals overall in all of my UOAs, making them look better than what that engine would look like with a normal 4-5 quart system.
 
It's really hard to say if Al is an issue or not. If it drops next time, I think you are ok. Everything else looks good. I'm skeptical of UOA's to begin with.
 
Originally Posted By: buster
It's really hard to say if Al is an issue or not. If it drops next time, I think you are ok. Everything else looks good. I'm skeptical of UOA's to begin with.


Buster,
I think you are right about UOAs. Good for showing Anti freeze if you are loosing water.
 
Originally Posted By: buster
It's really hard to say if Al is an issue or not. If it drops next time, I think you are ok. Everything else looks good. I'm skeptical of UOA's to begin with.


The one thing that does kinda scare me is that Wearcheck has been pretty consistent with the results they've given me on this car over the past 5 years. The wear numbers have been roughly the same all along, and even looking at the additive levels since I started using PP 5w30 you can see that it stays roughly the same each time too. So it's most likely true that aluminum is rising.

But even if aluminum is really starting to rise on me, what can I honestly do about it? I certainly can't afford to tear down the engine and dig into it right now, and even if I could afford it I doubt I'd bother, I'd just let the engine slowly destroy itself and then throw in a brand new 430hp LS3 engine.
grin2.gif
 
Not much you could do with oil. It could be the coating has worn through on the piston skirts if your pistons were coated like alot of the shorter skirted pistons are these days. I haven't heard of this happening but just brainstorming a possible causal factor on where the aluminum came from.
You would need to expose aluminum to friction through a particle streak (it could have been caught by the filter on the first pass but scored a piston) or surfaces that normally didn't encounter friction have begun to experience friction.

A compression check is a quick way to see if there is a ring issue.
 
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Let me think this over. The LS design is OHV meaning you should have a Forged Cam sitting inside the block(aluminum but should have bearings supporting the cam. The heads are aluminum with rockers seated in them... it is a possibility. I understand the timing chain is pretty short, is it possible there is a wear and tear item (like Old Toyota chain tensioners) that would allow the chain to rub the block?
 
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