Mostly Mechanical

Auto & Truck Oils, Lubes & Filters – Separating Technology from Hype

How to pick an aftermarket air intake filter that removes dust?

The ads all sound great, but what’s the bare truth?  Most consumers have no idea how to identify and separate marketing smoke-blowers from engineered excellent performance.  So, I’m going to tell you.

Several manufacturers of aftermarket air intake filters make great-sounding claims about how well their engine air intake filters remove the fine, sandy grit that causes engine wear.  It’s good they’re at least making some claims, because most of the worst performers just ignore the issue of wear particles that pass through their filters.  (That’s a consumer hint – don’t buy filters that don’t even attempt to tell you how well they perform.) But how great do those filters really perform in removing dust wear particles? 

One company boasts an ISO 5011 test stand with certified performance that’s “testing to the highest standards”.  Sounds great.  Another uses filter media designed Nanofiber web overlaid on standard cellulose substratewith 5 layers of progressive filtering that’s 99.4% efficient, and “so revolutionary that we applied for and received a patent.”  These filters are probably better than the OEM and OEM-style paper filters.  But what’s the best performance?  As an automotive engineer, I’m adamant in recommending nanofiber filtration technology that’s 98.7% efficient at 2 microns, and 100% efficient at 3 microns.  But 99.4% looks like a better number than 98.7%, right?  So why do I recommend something that appears to be worse performance, and how do I know that nanofiber technology is really better?  Stick with me a couple of minutes to sweep away the fogs of consumer deception, and I’ll explain.

There are four things that count in air filtration:  flow volume, holding capacity, and filtration particle size at a specific efficiency.

  1. Flow Volume.  Some companies focus exclusively on flow volume. 
    Three things to beware:
    – Flow volume at what pressure drop? 
    – What’s your engine’s maximum airflow?  Any flow beyond what your engine can use is useless to you.  In racing or pulling applications with modified vehicles, a high pressure drop (because of high air flow volume) can often collapse the filter.  The engine-damaging results are expensive. 
    – Very low pressure drop at very high flow usually means that at least 50% of meaningful wear particles are passing right through into your engine.
  2. Holding capacity.  How much particulate will the filter hold before the pressure drop across the filter is measureably reducing your fuel economy or power?  In the case of oiled-cotton-gauze filters, how much particulate will the filter hold before it’s passing nearly all the wear particles into your engine?  (The classic answer is “not much”.)
  3. Filtration Particle Size.  The accepted engineering rule of thumb is that damaging wear particles are those with a size of 5 to 25 microns.  Filtering smaller ones is icing on the cake.  Claiming filter performance efficiency on particles larger than 20 microns is a warning sign that the filter performance is very poor.
  4. Filtration Efficiency.  This is listed as a percentage, which refers to what percent of a certain size of particles are captured by the filter.  Beware: in order for either the particle-size or efficiency to have ANY meaning at all, you MUST know both numbers.  Any company who quotes one without the other is simply trying to deceive you, and generally implies that their real performance in removing wear particles is average to poor.

  So that’s the bottom line.  What matters is that AMSOIL’s Ea line of nanofiber air filters is 98.7% efficient at 2 microns.  According to an SAE research paper, that level of filtration reduces particle-based engine wear to levels so low that it is difficult to detect any wear.

What about certified ISO testing?  That’s all legitimately potentially impressive, but “the devil’s in the details”.  What’s the particle size at what efficiency percentage?  They don’t tell you, so you have to figure it out.  That’s pretty tough if you aren’t a trained engineer… and not very convenient for consumers!  For example, an “SAE  Coarse Dust Test” uses A4, and if you look at a typical sample of certified test dust (sent to me by a filter company that advertises their ISO testing), you find that more than 85% of the test dust is larger than 10 microns, less than 35% is smaller than 20 microns in size, and particles that are 5 microns or smaller are less than 10% of the dust. So, “coarse dust” does a poor job in both representing typical driving exposure, AND in representing the 5 to 25 micron wear-particle range that is so critical to your engine.

So what does that mean?  A couple of very important things. 
First, “coarse” test dust is exactly that, and it’s not going to tell you much other than that you have a filter.  It’s a good test of how well your filter will work in a baja race if you’re eating a lot of dust kicked up in front of you.  But is that what you’re doing?  If they really wanted to test and demonstrate meaningful performance, they would use “fine” test dust. 
Secondly, it means that when they do comparison “side by side” “apples to apples” testing against a much better filter, like a nanofiber media, their filter performance can look very good – even identical.  Because as the coarse dust builds up on their coarse filter, the classic “dust cake” forms, enabling the filter to take out much smaller particles than it otherwise could. If they tested it with fine dust, the results would be very different.

AMSOIL doesn’t play games.  Ea filters are tested with fine dust by the most respected certified filtration test lab in the nation, and they publish the particle size and efficiency together with flow and capacity data.  They tell us everything, nothing hidden.  No-one else does that.  15 times the dust holding capacity of oiled gauze filters, at an identical (very low) 0.5 inches of pressure drop.  And just try to beat 98.7% at 2 microns.  Ain’t gonna happen.M1A1 Abrams main battle tank in a cloud of dust

By the way, nanofiber filters don’t use oil, are quickly re-cleanable and re-useable, and are also cheaper to use than any other filter solution.  Yeh.  Use nanofiber and win on time, win on cost, win on performance.  Who can beat that?

The U.S. Army must agree with me, because nanofiber filtration technology is what the M1A1 Abrams battle tank has been using for more than a decade. 

April 4, 2008 Posted by | Amsoil, Diesel, Diesels, Engine Air Filtration, Filtration Technologies, Vehicle Maintenance | , , , | 6 Comments

Differential Fluids, Differential Covers, and Towing.

OK, what’s the real scoop on differentials?  What do aftermarket differential covers do for you?  Should you buy one or make it yourself?  When should you worry about it?  When do you need a temperature gauge for your differential?  Those questions and more came up in a recent online user forum, and the experts’ answers were excellent.  If you do any towing, I believe this information is critical for you.

OEM’s agree that to maximize your differential life you need to do your first fluid change at 5,000 miles, and lubrication and drivetrain engineers will add that a high-performance synthetic is the best and longest-lasting choice.  Maybe you’ve heard that, but what synthetic should you choose?  Remarkably, there are downright embarrassing differences in the tested performance of gear lubes on the market.   In fact, using the wrong one in a towing application will probably take your differential into early failure.   You can download a free research study detailing the performance testing of 14 name-brand gear lubes.  Think it doesn’t matter much?  On the contrary, we found it very disturbing that over half of the name-brand gear lubes failed one or more of the standard performance tests.

That study is also excellent because at the beginning, as background, it outlines the results of operating-temperature studies done on differentials in towing applications.  The information from those studies is eye-opening.  So enjoy.  And remember, your entire vehicle and towing load rests on TWO GEAR TEETH in your differential: your gear lube choice is critical !

February 25, 2008 Posted by | Amsoil, Diesel, Diesels, Fleet, Lubrication Oils & Fluids, Vehicle Maintenance | , , , , , , | 2 Comments

Authoritative Global-Warming Conclusions: Wake up EPA !

It appears that scientists are continuing to learn a lot more about what actually causes climactic variations. In fact, it’s gotten to the point where perhaps a majority of scientists are outright calling Global Warming and Greenhouse gases a “scam”. Why are these types of positions being taken, even while others are still calling global warming “unequivocal” and treating it as a sky-is-falling fact of tragic proportion?

It appears that those still promoting global warming aren’t keeping up with the data. Two of the best recent examples cover the logic, the issues, and the scientific mechanisms that are driving the most up-to-date scientific opinions:

A recent article in the International Journal of Climatology of the Royal Meteorological Society is detailed here:

This one – “Global Warming not Affected by Man” covers more detail:

“The late New Zealand professor Augie Auer explained that three-quarters of the planet is ocean, and 95 percent of the greenhouse effect is governed by water vapour.

“Of that remaining 5 percent, only about 3.6 percent is governed by CO2 and when you break it down even further, studies have shown that the anthropogenic (man-made) contribution to CO2 versus the natural is about 3.2 percent.”

“So if you multiply the total contribution 3.6 by the man-made portion of it, 3.2, you find out that the anthropogenic contribution of CO2 to the the global greenhouse effect is 0.115 percent … that’s like .12 cents in $100. It’s minuscule … it’s nothing. “”

I like to point out a couple of common sense things that seem to escape many people. First, that naturally-caused forest fires generate huge amounts of oxide emissions, and mankind already does a great deal to prevent and extinquish such fires – that alone does a lot to reduce our “carbon footprint”. And second, mankind’s worldwide activities can’t hold a candle to the output from a volcanic eruption.

Finally, the scientific research is getting to the point where it can effectively explain common sense. So back to diesels: Mr. EPA, how about rolling back the greenhouse gas emissions requirements set in place for 2007 vehicles, and unleashing modern diesels to get a 10% fuel economy improvement? Isn’t saving 10% in fuel economy more environmentally responsible than reducing gas emissions that have no measurable environmental impact?

February 23, 2008 Posted by | Diesel, Environment, Environmental Issues, Fraud Alert, Fuel Economy, Global Warming | , , , , | 2 Comments