Wayne, I understand what you're saying. Me personally, I've never done one, but I am going to mid-summer.

For a guy like me who may not notice the symptoms for many things, oil analysis can be beneficial. I'm not going to do it often and I may never do it again on my Rodeo. I am curious as to what the data will be. Another reason I want to do it is it seems interesting and in an odd way, fun.

Most ppl who use oil analysis probably do so on a consistent basis. Pointless, random sampling won't really let you spot trends...

The lab (Blackstone) has a database (rather large!) of all the samples it has analyzed, and the AVERAGE data for YOUR type of engine is included with, and compared against your current sample data. Thus, you DO have a "baseline" to compare to. So, when you see "xxx" ppm of copper in your sample, and it is much higher than the average, you can be somewhat sure that there is some abnormal bearing wear occuring. (aren't most engine bearings basically the same composition? copper, lead, tin, etc ?)

When you submit your sample, you are instructed to indicate the "service miles" of the sample. So, 1000 vs 4000 miles doesn't really matter. It's all factored into the results.

Bottom line is that a random (say yearly) sample won't be of as much value as one every oil change, but can give you data that is relevant to the general condition of your engine. I think you would have to be pretty "retentive" to want to sample at every change.

I'm getting ready to send a sample in soon, the first oil change after changing out my head. I'm mainly interested in anti-freeze intrusion, and they can detect very small amounts. As you probably know, anti-freeze will trash your bearings in a hurry!

Those tests can tell you when the oil has broken down and no longer provides the same level of protection as new oil. That way you can establish your own change interval with data to support it. No one that I have read about is looking at those charts and checking for engine damage but I suppose if you wanted to get technical you could.

And most of the guys doing the "extended oil change intervals" are running expensive bypass filter setups.

One thing I find odd about this strategy is that those filter setups cost quite a few hundred bucks... and the analysis is $20 a pop. Doesn't seem economically sound to me. I could just change my oil and filter for the price of the analysis!

Now, if you own an OTR trucking company, you could probably save some bucks. But an average Joe Driver? I doubt it.

one thing a lot of people are forgetting is it is a hobby to some. Some of those guys are running the tests because it is enjoyable for them. Over on BITOG, it's a sickness how much people love oil( i mean that in a good way, I too enjoy that forum). Most people who are doing it probably don't need to, but they like to or feel it provides an added measure of protection.

A lot of those guys on BITOG are doing it just as much as anything to see the wear metals and what not. They are doing it for all of the info, sure some are doing it to see how much their oil has left, but my impression is many are doing it to see if there is a coolant leak or any engine abnormalities.

marc

I personally haven't used Blackstone for anything but my diesel and when a oil change means 15qts of syn the 20 bucks is less of a big deal. I have made it over 12k so far on my last change without having a dual bypass. When I use them I don't Drain all of my oil either, it's just a qt or so, then get the sample. It's amazing the stuff that they can tell you about your engine and thats why i'm gonna keep doing the 20 bucks every 4k to see if I need to change my oil.

I have a friend who has a 4.3l and he is at around 10k on his last oil change. By using Blackstone.

It's all a give and take. If your putting 2 qts in between a 3k oil change interval then the 20 bucks probably isn't as good of a deal, however a once a year test on the oil might be good to see whats going on in the engine based on your last sample.

Another case that makes sense to use testing that I didn't notice mentioned is when you purchase a new vehicle. That would give you some idea of the condition of the motor, and if you got a good deal or got took.

Here is an interesting fact I learned the other day at the GM dealership. Did you know that Synthetic oil will attack and breakdown any type of a RTV sealant?

That doesn't make sense to me. With the exception of gross failure, I would expect a vehicle with 150k miles and 500 miles after an oil change to have a much cleaner result than a vehicle with 25k miles and 5000 miles after an oil change. They should ask:
1. Service life
2. Miles since last oil and filter change.
And if they wanted to be real exact, they should ask the brand of oil to factor out the trace metals in it.


This is true, but:
1. Oil breakdown will vary by season and driving style (towing, hills, highway, city). At best, you get a rough estimate based on one brand/type of oil....which is what your manual (or common sense knowing how you've driven in the last three months) gives you.

2. I agree with the comment on cost. Having seen these done, I don't understand the setup fees past maybe $5 Ignoring them, it's a $20 fee you'll have to pay several times until you nail down the proper interval period (for that brand and type of oil, during that type of driving style). For $20, you can get a $6 filter and $14 Wal-Mart synthetic (or Shell Rotella Synthetic) and have a synthetic oil and filter change for the same price.

With the exception of some SAE data, and the consumer reports article, everything I read about oil changes is pure speculation. I agree that more frequent oil and filter changes will help extend engine life, but only up to a point (300 mile changes, anyone?). Every time the oil thread comes up, I ask for actual experiments and data to justify why oil changes should be done at X intervals, and why synthetic is so much better for normal (not race or high load/high temp) use, and no one can provide any.

That being said, I do use synthetic in my new Isuzu, but not in my old one.

I do agree with the oil/hobby comment--it's an obsession!--and the diesel comment, with 15qt oil changes, especially if you're using synthetic. Of course, then there's the question of why use synthetic for normal use again.