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© 2003 Brian F. Schreurs
Even we have a disclaimer.

In theory, of course, if you mail four identical bricks to four different brick-weighing facilities, each facility should come up with an identical weight. In our experience, however, that never happens.

We very much want to run a comparison of laboratories using our own test samples, but so far reader response for the idea has been, well, underwhelming. Fortunately for us, reader Paul Seminara has already conducted a similar test (paid for out of his own pocket!) and was kind enough to share the results with us.

Paul's car is a 1996 Volvo 850 wagon with a 2.5L inline-5 non-turbo engine; it has a 6.8-quart sump capacity. It started the test with 48,000 miles, and ran Amsoil 5W30 synthetic oil (the same stuff we're going to use) for 20,000 miles. He changed the oil filter every 5,000 miles and changed the air filter at 15,000 miles. He ran the car on 87 octane most of the time. Over the course of the sample period, he added 3.5 quarts of make-up oil. When he drained the oil, he took a large sample, split it four ways, and sent them to four labs. Here are his results:

	Blackstone Labs	ANA Labs	Oil Analyzers	Predictive Maintenance
Aluminum	4	5	4	4
Chromium	2	2	3	3
Iron	13	12	14	16
Copper	9	5	11	15
Lead	1	5	1	0
Tin	0	9	0	0
Molybdenum	3	<1	1	0
Nickel	0	<1	0	0
Manganese	6	—	—	—
Silver	0	<1	0	0
Titanium	0	<1	0	—
Vanadium	—	<1	0	—
Potassium	0	8	0	1
Cadmium	—	<1	—	—
Antimony	—	<1	—	—
Boron	4	4	3	3
Silicon	4	3	1	4
Sodium	3	<1	0	5
Calcium	2890	1799	2957	2447
Magnesium	334	316	380	342
Phosphorus	1101	942	1330	1513
Zinc	1521	1027	1490	1856
Barium	0	<1	2	—
Viscosity	60.9	11.79	10.16	10.1
Flashpoint	365	—	—	—
Fuel	<0.5%	<0.5%	<1%	A
Antifreeze	0.0%	None	None	None
Water	0.0%	<0.05%	0%	0.1%
Soot	—	<0.2%	N/A	<0.1
Insolubles	0.4%	—	—	—
SAE Grade	—	530	—	—
Oxidation	—	—	25.0	58.001
Nitration	—	—	26.0	5.40
TBN	5.0	3.20	3.88	3.33

It's worth noting right off the bat that two apparent discrepancies in the Blackstone report actually reflect different test procedures: the viscosity, using our handy viscosity converter, is 10.46 using the same units as the other labs; the TBN is tested using a different methodology entirely and is not really comparable to the other labs. Also, Oil Analyzers and Predicitive Maintenance use different test methods for checking oxidation and nitration, so those numbers are not directly comparable either.

Comparing the discrepancies in the testing to the tolerances noted in the Margins of Error article shows that, for the most part, any of these labs is capable of successfully analyzing oil. The only lab that gives us pause is ANA Labs, who got a couple of wild numbers in the spectrometric analysis and completely blew it in the viscosity test.

Blackstone's delivered price (including all options and shipping) was $31.48; ANA Labs was $25.00; Oil Analyzers was $18.95; and Predictive Maintenance was $32.62. As far as value for the dollar, Blackstone looks pretty good. They're only skipping three elements in the spectrometric analysis, and those are pretty unimportant elements if the results from the other labs are any indication. We might have liked the viscosity to be a bit closer than it was, and it's frustrating that they use a different TBN methodology from everyone else. It also would be helpful if they would include oxidation and nitration. But we were surprised to find they were the only lab testing for insolubles, as that is a good indicator of when to change the oil filter. And their results have consistently held up to close scrutiny. On a subjective note, the commentary they add with each analysis is great, and the comparison to the car's own averages and overall averages for the type of car is pretty nice. Oil Analyzers fares well too, especially considering the comparatively low cost, but the lack of

Honor Roll ANA Labs maybe you? Blackstone Brian Schreurs Dyson maybe you? Oil Analyzers maybe you? Predictive maybe you? WearCheck maybe you?

insolubles and flashpoint testing is disappointing (and you do have to get past the very close association with Amsoil).

We're very grateful to Paul for sharing his test data, but we'd still like to do a comparison using numbers from our own test car. So, the plan is to select one of the oil-flush intervals between oil types for drawing samples. This way each lab is receiving oil from the same batch. When we get the results from all labs, we'll post a detailed comparison here.

All we need are some volunteers to help defray the cost of the extra analyses. They're around $20 each; write us if you're interested in helping us out.

The labs we will evaluate are: ANA Laboratories, Blackstone Laboratories, Dyson Analysis, Oil Analyzers, Predictive Maintenance, and WearCheck. If we're missing a lab that should be included, let us know.