Posted: Mar 17 2008 at 1:00pm | IP Logged

First let me answer dannyg's question, you can find oil analysis testing labs all over the country, I am not sure if there are any in FL, but you can do an internet search and probably come up with a whole list of labs that might do private consumer testing. A couple off the bat are Blackstone Labs, Oil Analyzers that are the more popular in the US. You could find more and compare prices, they will send you a kit for free usually to sample your oil and ship it back to them. It just depends on the lab.

S.A.R Tech:

Thanks for posting your numbers, as I said mine will be taking a little bit longer, but if I get my new drain plug from which I can try to get a sample it might come sooner than that. I'm only at around just over 4000 miles. Now let's get down and dirty with your analysis.

What was the only thing they flagged for wear metals? Copper is slightly elevated but could be from radiator corrosion (if you still had a coolant leak or suspect one). However your potassium levels are very low, which sometimes go hand in hand with elevated sodium in coolant leaks. So your baseline UOA was showing 62 for sodium and you are down one ppm now. I tried looking for the original numbers, I know you indicated that they zeroed some numbers out but what was the original sodium number on the Virgin sample of Amsoil? Nissan's oil is most likely a bulk oil that the dealer can get cheap, I know around here last tiem I took my sister's Xterra in for her free oil change it was Quaker State. However, the dealer might just buy whatever is cheapest in bulk. I wouldn't be able to tell you what the levels of sodium in those samples are, but you might be correct. Are you still having a coolant drop in your truck? Other sources of copper are bearing and bushing, as well as an oil cooler if you had one that would be passivating Cu into your oil. They still look w/in acceptable limits from what I've seen.

Your Fe levels look fantastic for going that long on the oil, about 7500 miles from my calculations. From my understanding you aren't getting a lot of Fe wear and/or your oil filter is doing a great job.

Si levels are elevated but you said you do a lot of dirty road/dusty road driving IIRC.

Everything else looks pretty good from my understanding. What was the 100C viscosity on the new sample? I'm curious to see if the oil sheared down any after that long of a run.

Was the TAN number on this sample? The initial TBN of 12.20 is very good and typical of Amsoil from my understanding as you'd expect for an oil that is supposed to have the ability to go long drains. Did you get a TBN on this UOA?

Thanks.

Posted: Mar 18 2008 at 1:01am | IP Logged

S.A.R.Tech wrote: They didn't flag any wear metals, just the Na, again. But as you can see, it has dropped. This confirms that it was not from a coolant concern, just the old nissan oil. Coupled with the fact that I have been watching my coolant levels very carefully since the 1st sample.

That is very interesting, that is good that you have kept an eye on your coolant level, and just makes me wonder what oil your dealer was using that it has hung around in those levels for this long. As far as I know, even as an additive,  that is pretty high. The other thing is, the fact that it dropped by only 1ppm isn't a really big deal, as "noise levels" depending on their analysis method, whether it be by ICP-optical emission spectrometry or by atomic absorbtion spec. I've had samples run twice before on the same exact sample and had a variance of 1-2 ppm. That isn't uncommon. However, that being said, as long as it's going down, that's a good thing.

[/QUOTE] The levels that concerned me were the Cu, Al, and Cr.
Al has sextupled! That seems like a lot. Could this all be from the
casting? [/QUOTE]

As I had mentioned before, it was also interesting that they didn't flag the Cu, granted it is still w/in "acceptable" limits, but it would also worry me. Al and Cr were very very low, and could also be noise, though, I would figure that more on the Cr reading than the Al, but your Al reading are well w/in the limits I've read about, just keep an eye on it in future UOA's.

[/QUOTE]
The new sample 100deg viscosity was 9.8, then 9.3, then 9.7. How does
it go down then up again? [/QUOTE] 

There are several reasons, that it could go down then up. Method variances, any deviation from D445, having used a CAV (automatic viscometer) I can tell you that for whatever reason, they can just do something wierd at times if they get an air bubble in the oil or whatnot, and just give a wacky reading, but when you rerun a sample it would look normal. I would think that the lab techs would catch something like that and rerun accordingly to ensure accuracy. Since you are only topping off with a very minute amount of oil, a few oz. I'm assuming it shouldn't have that big of an effect on the viscosity. Another reason viscosity could go down is shearing like I mentioned before. Oil being abused by the high shear areas in an engine (b/w cylinder and wall, bearings, etc.) Viscosity could go back up, with contamination causing oil to carry more insolubles such as dirt (Si).

[/QUOTE]
I was only given TAN and TBN on the new oil sample I provided them for
a baseline.
[/QUOTE]  It would have been nice to see a TBN on this sample to see how much active neutralizing power the oil had left in it, does it cost more to add a TBN?

Posted: Jun 15 2008 at 1:20pm | IP Logged

Ok, I know it's taken awhile to get to my drain, and I had drained my oil a few weeks ago, but I had to wait til the funds became available to send the sample off. I believe I have mid 5000m on this OCI. The USPS indicated it had to go ground, so about 6 days shipping time to the lab. I shipped it this past Monday. Hopefully sometime this week I will have results. I am very interested to see what my analysis will look like, if I don't like the looks of it. I might  be able to get another analysis done to have a check on the original analysis. As mentioned before, I believe I still might be dealing with a coolant issue. I think this was the M1 Mix that I had, with a slight (1/16-1/4 qt) makeup with 10W-30 Castrol GTX High Mileage. I don't even know for sure that I needed the make up, as the stupid dipsticks that these older Frontiers have are stupid to read. Anyway, just a heads up about upcoming OCI results.