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

Global Warming – Fact or Fraud?

Global warming concerns: these days, they drive many decisions that are made daily by private citizens and public policy makers.  But as an engineer, I’ve long been suspicious about the idea of NOx (Nitrous Oxide) tailpipe emissions being anything more warming than the Nitrogen and Oxygen already in the atmousphere.  As a matter of fact, I’ve been very suspicious about the validity of any of it…  but I’m not a climate scientist.  

However, recently I’ve found scientists who are speaking out on this subject.  And wouldn’t you guess?  It’s all about the money, and those many people and nations who would like to destroy our Republic (no, the United States is not a democracy).  Other countries want to strangle us (and Western Civilization) with stringent and costly regulations that they have no intention of following themselves, because to them it’s nothing more than economic warfare.

Well over 10 Billion dollars has been spent on climate studies in the last 5 years.  Know what the facts say?  Global warming is mostly about FRAUD.  Costly, and potentially dangerous fraud.

Also check out this link:

So it turns out that I’m exactly right about the new ridiculously strict EPA regulations on diesel emissions that take effect for 2007 diesels and diesel fuels:  there is no more environmental protection to be gained from these tailpipe edicts than from regulating the content of cow manure emissions.   Think about the implications of that fact.


Feb 22nd Update:  Inel offered some interesting observations and perspectives.  And the eloquent and persuasive writing has prompted me to investigate further and respond.   Continue reading

January 5, 2007 Posted by | Diesels, Environment, Environmental Issues, Fraud Alert | 6 Comments

CJ-4 Diesel Oils only for 2007 & later models – they’re NOT for earlier diesels!

DO NOT use CJ-4 oil in vehicles prior to 2007 models, unless you want increased wear and more frequent oil changes: because the 2006 and earlier models do not have diesel particulate filters (DPF’s), they do not need the restricted formulation of these CJ-4 oils. 

Amsoil’s new DEO oil is a premium 5W-40 synthetic diesel engine oil that is certainly among the best examples of the new CJ-4 emissions-spec oils.   In fact, it’s one of the only examples: most oil companies still don’t have a CJ-4 diesel engine oil formulation, much less have it available in the U.S. market as of October 2006.  Even more kudos to Amsoil, because their CJ-4 oil performance is still better than most CI-4+ oils, and because it’s proven – it has already logged over 12 million fleet miles.

To be fair, this article title isn’t completely true:  if you’re changing your fleet over to Amsoil and take it all to CJ-4 so that you can be certain of always using a DPF-compatible oil, you are still getting a better performing oil across your entire fleet than your current petroleum CI-4+ oil.  So don’t take me wrong.  

But while this CJ-4 oil is the best that Amsoil can formulate within the specification requirements, and it is the best performer available in this group, the CJ-4 spec does compromise oil performance with brand-new limitations on the oil additive contents.   This is why Amsoil only recommends DEO “for use according to the longest service interval established by the engine, vehicle or equipment manufacturer”: there is concern that the additive package cannot handle the dramatically extended (25,000+ mile) drain intervals with the conservative safety margins that Amsoil’s other diesel oils are designed for.   Oil sampling analysis will be a more essential element than ever before in fleet management for 2007+ diesels.  

So in 2006 and earlier model diesels, always use the 15W-40 (AME) or the high-fuel-efficiency 5W-30 (HDD) if your goal is to maximize fuel economy and engine life while minimizing your maintenance costs.  Amsoil will NOT be discontinuing these CI-4+ oils anytime in the foreseeable future.

Which oil should you use for 2006 and earlier diesel models?

The two best choices on the market – per the published technical performance test data, field fleet testing, and product warranty – are the Amsoil 15W-40 Premium Heavy Duty Diesel & Marine oil (product code AME), or the Amsoil Series 3000 5W-30 Heavy Duty Diesel Motor Oil (product HDD).  Despite your owner’s manual recommendation of a 15W-40 oil, your PowerStroke/Duramax/Cummins/Volvo/Caterpillar engine – like nearly all engines – is designed to use a 30-weight oil.  The 15W-40 recommendation is not based on engine design, but on the assumption that 40-weight petroleum oils will often “shear back” to a 30-weight oil in diesels, and if you use a 30-weight oil that shears back to a 20-weight oil you will have wear problems (or worse).  Of course, AMSOIL’s full PAO synthetic HDD formulation will maintain viscosity as long as you are using it as recommended in a healthy engine (no fuel getting in the oil, for example) – so your engine will enjoy year-round benefit from the 30-weight oil it was designed for. 


Both oils are 25,000 mile oils that outperform every other available diesel oil on the market, and are LESS EXPENSIVE to use because of those extended drain intervals.  Both oils are also superb performers in gasoline engines.  Either oil will work well for you, but my best recommendation is for you to make an informed choice based on your specific needs.  Here are some suggestions to help you:


        For this Application…                                         Pick this oil:

             Fuel Economy                                           Series 3000 5W-30 (HDD)

    Cold Temperature Performance                             Series 3000 5W-30 (HDD)

    All-fleet oil for home/farm/garden                          Series 3000 5W-30 (HDD)

            Lowest oil usage                                              15W-40 (AME)

          OTR Freight Hauling                                 5W-30 (HDD) – or 15W-40 (AME)*

       All-fleet oil for class 3-8                              15W-40 (AME) – or 5W-30 (HDD)*

All-purpose oil for logging/heavy-construction                    15W-40 (AME)*


*While it is difficult to compare them, Engineers generally agree the thicker 15W-40 (AME) will provide slightly more wear protection than 5W-30 (HDD) in extremely heavy applications, particularly off-road/gravel/rock-crawling applications where drivetrains are subject to heavy torsional shock-loading.  However, for highway/city mileage, HDD fuel economy savings probably exceed savings from reduced wear with AME – if there is any reduced wear at all with AME in highway/city driving.

More diesel info here

October 23, 2006 Posted by | Diesels, Lubrication Oils & Fluids, Vehicle Maintenance | 5 Comments

2007 Diesel Regulations – Environmental Irresponsibility?

2007 Diesel-engine vehicles are all about an expensive attempt to meet the new EPA regulations by using high EGR percentages, Diesel Particulate Filters, CJ-4 motor oil specifications, and Ultra Low Sulfur diesel fuel.  Now, all this has increased the cost of fuel, reduced fuel economy by 10% (burning MORE non-renewable resources!), increased engine wear rates, and – one can argue – may well increase the amount of used motor oil dumped in the environment, which has a highly negative environmental impact.  So the questions need to be asked: Does the EPA’s strict new diesel emissions regulations really benefit the environment, or does it create a heavier environmental impact?   How important is it to feel good about ridiculously low NOx emission levels which have no demonstrable benefit? 

This could get quite technical, but I’ll keep it simple.  For low engine wear rates (prolonging vehicle life, and reducing both oil consumption and maintenance costs), you must control soot and acid content in the diesel motor oil.  Good levels of ZDDP (a Zinc compound) and sulfated ash are clearly the best and most effective ways to achieve those goals, producing low wear rates and high TBN’s (total base number) for neutralizing acids.  Having plenty of ZDDP and high TBN in a high-quality synthetic oil base-stock means that oil change intervals can be dramatically extended to 25,000 miles in typical diesel pickups, or – by adding bypass filtration systems – oil changes can be completely eliminated.  Amsoil turned this technology into a proven science decades ago, which has been proven in extensive oil analysis sampling and fleet engine rebuild results, and has been repeatedly noted for the strong environmental benefits: 25,000 mile oil change intervals produce more than an 87% reduction in motor oil useage.  The environmental benefits of “extended drain” oil and filter technologies include increased fuel economy, dramatic reductions in the amount of “dumped” used oil and of filters disposed, and improved vehicle emissions.

Unfortunately, the new CJ-4 spec places strict limits on what you can use to get good TBN, keep the engine clean (minimizing emissions increases), increase fuel economy, and reduce wear  – essentially it cripples the oil formulation so that we can’t get what we need for best use of resources.   Amsoil played a vital role in writing this spec, which is what made it possible for the vehicle OEM’s to meet the new EPA emissions reg’s and not destroy their engines or emissions equipment before the warranty is up (they hope).

The issue all goes back to NOx emissions: that’s the first “domino” in the chain, and I’ll walk you down the chain from link to link.  Both Oxygen and Nitrogen are abundantly present in the air anyway.  So the environmental importance of extremely low NOx emissions is highly questionable in my opinion (and I’m not alone in this).  Apart from this, the newer 2002+ diesels are VERY clean and environmentally friendly.  However, based on an assumed importance for extremely low NOx, the EGR (exhaust gas recirculation) rates had to be dramatically increased – from a typical 10-15% for the earlier EPA standards, to an amazing 25-35%.  The proof of the technical ridiculousness of this is not that it creates hotter-running engines, but that it results in about a 10% reduction in diesel fuel economy – much of that due to a lot of unburned fuel that exits the exhaust (“soot” as black smoke).  That’s where the diesel particulate filters (DPF’s) come in: these are required in order to trap the soot (unburned fuel), then periodically burn off that unburned fuel – by consuming more fuel.  Once you do all that, you now have exhaust that is both clean AND extremely low in NOx emissions.

Now, you might say “wait a minute.  Do I understand correctly that in order to reduce NOx emissions, they are increasing fuel consumption by 10% – trading a small and very questionable environmental improvement for a 10% increase in the amount of fuel used?”  Yes.  You’ve got the environmental picture so far, except that the story gets worse. 

The DPF’s typically contain SCR technology (Selective Catalyst Reduction), which is a catalytic converter for diesels.  These “cat bricks” will slowly plug up from deposited solids that can’t be burned off, while the fuel economy will get worse and worse as the exhaust backpressure continues to increase.  OEM’s are hoping that they’ll “last” 150,000 miles before the fuel economy gets absurdly bad, but no-one really knows.  Many are concerned about the public backlash when people find out how ridiculously expensive it’s going to be to service or replace these units.  The main factors determining the effective life of an SCR/DPF are fuel quality, engine oil content, and the amount of engine oil that is burned.  (In other words, if you want to keep good fuel economy and avoid expensive repairs on a 2007 diesel for as long as possible, pay close attention!) 

Due to the sensitive nature of the DPF’s, automakers had to reduce every possible source of deposits that could kill DPF performance over time – primarily these two sources:

1) Sulfur in the fuel.  This was dropped from 5,000 ppm (parts per million) to 500 ppm in 1994 with the Low Sulfur Diesel (LSD), and now again in 2006 and 2007 – down to an unbelievable 15 ppm with Ultra Low Sulfer Diesel (ULSD).  Why is this bad?  Not because it’s a pollutant, but because it slowly plugs your DPF.  That’s why you DO NOT want to use LSD in a 2007 or later diesel: it kills your DPF 33 times faster. 

Problem is, the Sulfur is an important lubricant for the fuel injector pump and the fuel injectors, and Europe’s experience proved the ULSD puts these expensive components in a junkyard in far less than half their normal life.  U.S. experts don’t think the federal regulations will do much to ensure that fuel-station owners and attendants will remember to dose the diesel with the correct level of lubrication additives.  So a word to the wise: put your own additive into your fuel tank during every fillup!

2) Sulfated ash, Phosphorus, Sulfur, and Zinc in engine oils.  Those contents all play key roles in oil performance, but now they must be restricted.  Because after all, a very slight amount of oil does get consumed in the engine and exits through the exhaust.  And with higher EGR rates, even more oil is likely to be burned.  Again, the problem with each of these four is that they accumulate in the DPF catalyst “brick” and plug it up.

By severely limiting these elements and compounds in the motor oil, the performance capability of the oil has been limited.  And to a great extent, the use of synthetic oils becomes almost essential.  But whether synthetics or fossil-oil, this logically means that the diesel engine oil must be changed more frequently than would otherwise be needed, again consuming more natural resources that are non-renewable, and probably increasing the amount of used oil dumped in the environment.

Specifically, the CJ-4 oils are limited in their capability to reduce wear, to control/disperse soot, and to neutralize acids.  The soot and acid issue means that premium synthetics are limited to lower maximum extended drain intervals. At the same time, the higher EGR rates are producing more soot and more acid in the oil, both of which are proven to reduce engine life.  So oil performance and engine life have both been compromised by these CJ-4 requirements.  To better see what I mean, compare the specs for AMSOIL’s new CJ-4 diesel oil, with the flagship CI-4 Plus Diesel Oil: the new CJ-4 doesn’t perform near as well in the NOACK volatility or the 4-Ball Wear Test, and check out the huge difference in TBN’s.

Kudos to Amsoil, not only because their CJ-4 oil performance is still better than most CI-4+ oils, but because it’s available and has already logged over 12 million fleet miles: most oil companies still don’t have a CJ-4 diesel engine oil formulation, much less have it available in the U.S. market as of October 2006. 

So here are the cards we’ve turned over: the risk of increased motor-oil dumping, an additional 10% fuel consumption penalty (that just gets worse as the DPF back-pressure increases), an additional $700-7,000 per vehicle for the technology, and reduced engine life (at least compared to what it would otherwise be, not accounting for tribology advances that may offset the difference now or in the future).  Now that all those cards are on the table, who wins?   Does this make any environmental sense?  Are those penalties really justified merely in order to take very low NOx emissions to an extremely low level? 

Why did sales of 2006 diesels skyrocket as large fleets pushed to replace all older equipment with 2006 models?  Because the people who know the situation are deeply concerned about the large negative impact of these new regulations on our businesses and economy.  And don’t let the media fool you – the people who pay the bill for ALL of this are us – the consumers, and the taxpayers.

Knock, knock, EPA – is anyone with a brain at home?  Why would responsible environmental groups push for such results or support them?  Sounds like lunacy to me.  Has the EPA abandoned being an Environmental Protection Agency?  Since when did Congress vote to make them a Politically Correct Regulation Agency?  I vote for rolling back the 2007 NOx diesel emissions requirements, in order to reduce diesel fuel consumption by 10%, reduce the cost of the vehicles, reduce vehicle maintenance, extend vehicle life, and not force everyone to waste money to harm the environment while pretending to help it.  Anyone else on the side of sanity and holding government agencies responsible for their assigned roles?

Update on environmental FRAUD: 

October 23, 2006 Posted by | Diesels, Environment, Environmental Issues, Lubrication Oils & Fluids | 11 Comments