The Line on Lubricants
Lubricants keep friction from killing reciprocating and rotating parts. They are used in the engine, transmission, differential, wheel bearings,steering knuckles, power steering, air conditioning, other bearings (even the HVAC blower motor), and although not obvious when considering fuel economy, brake fluid. In most cases, the lubricant can be serviced — like an oil change. In some cases, lubrication is added at the point of manufacture and cannot be serviced (sealed bearings). This section deals with lubricant viscosity, quality, and additives.
Oil Classifications
Lubricants are categorized as petroleum based (dubbed “dino” oils, as in dead dinosaur derived oils), full synthetic, or synthetic blends. Way back when, oils were extracted from crude oil through a rudimentary distillation process (see illustration above). Depending on the quality of the crude oil, you got what you got (for what it was worth). Oil companies discovered over time, additives could get their oils to work better. Chemistries improved where they could orchestrate molecular densities to get base lubricant oils more consistent from one batch to the next, and from one crude source/batch to the next. Then came synthetics.
Hands down, Amsoil has been the pioneer in synthetic lubricants from day one. They first appeared on the scene in the 1960’s. In the 1970’s, several other companies offered synthetic lubricants as an alternative to “dino” oils. Unfortunately, these other companies didn’t do the research and testing Amsoil had done, caused many engine failures, and got entwined in fatal court battles. Synthetic oils got a bad rap in the process. As we move into the 80's, Amsoil continued to improve their chemistry, backed by impressive research and testing. By the 1990’s, Mobile Oil had introduced their Mobile1 Synthetic oil, and we started seeing synthetic blends. In the mid-90’s, Mobile did a routine spin test of all competing brands. This is a “reverse engineering” process to see what the competition is doing. When they tested the Castrol Syntex, which was billed as a “synthetic blend”, they found 100% dino base oils — no synthetic oils at all!
Mobile sued Castrol for false advertising. Mobile presented their test data and assured the judge that Castrol was not selling a “synthetic blend”. Castrol countered with ASTM performance standards that clearly spelled out how a synthetic oil had to perform under clearly defined testing protocol. They then presented data showing their Syntex met or exceeded every one of the applicable ASTM standards. In short, the judge sided with Castrol. The next day oil companies everywhere were changing their formulas and/or labels.
Castrol’s secret ingredient was Conoco’s Hydra-cracked Petroleum Base Oils. Conoco spent $1B+ on a refinery that could refine crude oil and remove the sulphur. The kicker that swayed the judge was the fact that sulphur destroys seals, gaskets, and other engine parts. In an engine, the water in the blow-by gasses chemically combines with sulphur in the high heat environment to produce sulphuric acid, which eats away at the engine itself. Without sulphur, a dino oil could meet many ASTM synthetic performance standards. Motorcraft Oil used to be labeled a “Premium Petroleum-Based Engine Lubricant”. After the court case, Motorcraft changed its label to say “Synthetic Blend”. Mobile changed their Mobile1 formula using Conoco base oils to replace some of the more expensive pure synthetics. Many other companies responded similarly. Of course, Conoco made out financially from the whole quagmire. (Quick side note, low-sulphur diesel fuel is refined using Conoco’s Hydra-cracking method of removing sulphur.) Amsoil remained unaffected by the infamous court case -- they didn’t change their chemistry based on legislation.
In 1989 I was a technician at a small town Chrysler dealer. I got involved in a landmark “catastrophic engine failure” issue that resulted in the recall of hundreds of thousands of vehicles. The victim was a brand new Dodge Grand Caravan that experienced severe valve float, where the valve hit the piston and got bent. You may think this is totally unrelated to lubricants. What is relevant is the fact that when I pulled the oil pan (with only ~800 miles on the odometer), it had a 1/16” layer of milky sludge on the bottom. I never payed attention to what engine oil Chrysler used at the factory before this experience. But afterwards, I had to find out. It turns out Chrysler used Quaker State Pennsylvania grade engine oil. I swore to never use Quaker State — or Penzoil (both used Pennsylvania crude for their base oils) ever again! I learned they were high in paraffins.
Recent trips to my local NAPA store suggests I cannot even buy automotive grade 100% dino oils. Their low-price engine oil is a synthetic blend. Dino oils are only available for small engine (off-road) applications. In Japan, engine oils are organic based — like peanut oil! In Canada, engine oils must contain a minimum amount of recycled oil. These laws do not apply to high-end synthetic oils, though. OK, enough background. Let’s move forward.
I have used Amsoil products extensively for many years. Recently I found Royal Purple products to perform as well, or in one instance better than Amsoil. Either brand will probably protect friction parts as well as humanly possible.
Oil Chemistry
The latest API SN rated engine oils are devoid of one of those additives I eluded to earlier, zinc oxide. Flat tappet engines experience massive frictional forces where the cam lobe interacts with the lifter (tappet). Zinc oxide allows these engines to “not kill the camshaft”. Roller tappets have been use almost exclusively since the 1990’s, eliminating the need for the zinc oxide additive. The US EPA mandated the elimination of zinc oxide in engine oils (for the SN standard rating), because the zinc would mix with the intake air charge through the PCV system. Going out the exhaust, it coated the effective catalysts in the catalytic converter, reducing its efficiency over time. Submarines and trans-oceanic ships strap zinc bars to the hull to reduce rust formation. Zinc is a powerful catalyst in its own right, as it aggressively absorbs electrons. However, those same properties allow it to readily bond with, and coat the catalytic converter catalyst metals. If you have an older engine, your modern engine oil may be killing your camshaft! There are zinc additives available you can legally purchase to add to your oil to protect your camshaft, and some engine oil companies offer zinc oxide oils for older engines (without the SN rating).
In summary, using synthetic oils can extend oil changes (Amsoil claims 50k miles between oil changes with their oil and filter package), and allow lighter viscosities. Synthetic oils can be used in all of the vehicle’s lubrication systems. Of special note is brake fluid. DOT3 is the standard. It is a mature chemistry that has stood the test of time, and is preferred by most OEMs. DOT4 is akin to a “synthetic blend”. You can use DOT4 in place of DOT3 without any repercussions, and it may or may not deliver better braking power. However, DOT5 is like the “full synthetic” version. It is NOT chemically compatible with lesser (DOT3_4) chemistries. To switch from DOT3 or DOT4 to DOT5 requires a thorough flush of the brake’s hydraulic system. DOT5 advantages include aversion to absorbing moisture (did you ever bleed a brake system, or rebuild a caliper and encounter “slime”?), a powerful rust inhibitor (in part provided by its ability to not absorb moisture), and high temperature tolerance. DOT5 is more expensive, but standard on some high-end vehicles (BMW comes to mind).
Viscosities
Lubricating oils are rated by how thick they are. A 90w120 is about the consistency of molasses, while a 0w20 is about the consistency of sewing machine oil. I remember back in the 1970’s, the big thing was 20w50 oil; so thick it would protect the engine from anything. New cars are now using 0w20 synthetic oil. What should you use??
While we see engine oil viscosities getting thinner (0w8??), bearing clearances are also getting tighter with more consistent tolerances on newer engines. The argument that thicker oil better protects engines on start up is based on the residual film on friction parts when the oil pump isn’t yet working. The counter argument favoring thinner oils is that it takes far less time for the oil pump to deliver full pressure with the lighter oils. Furthermore, lighter oils take less engine horsepower to pump (reduced parasitic losses), and less power to plow through (windage). It’s like the difference between running on dry ground (air is extremely light in viscosity) versus trying to run in a swimming pool (where water has a much higher viscosity/windage).
The safe choice is to use the oil rating recommended in the owner’s manual. Older vehicles were recommend to use oils based on the ratings and quality available when manufactured. Newer chemistries may allow for lighter oils. A good example is an older engine recommending 10w30 oil. This is probably a “dino oil” rating. Upgrading to synthetics, a 5w30 (or maybe even 5w20) oil is probably perfectly safe. This will reduce parasitic losses from oil pump load. Another consideration is the condition of the engine. Thicker oils seep out of leaky seals and gaskets slower than do thinner oils. If the engine has notable oil leaks, moving to a heavier oil will reduce oil consumption — but at the expense of fuel economy and power. If the engine has a lot of miles, chances are the bearing clearances are sloppy from normal wear. Heavier oils may be needed to keep it from spinning a bearing.
Differentials and transmissions can benefit from lighter weight synthetic oils also. The differential may call for 90w120 gear oil. A synthetic 75w90 is probably just as effective at protecting the diff. Manual transmissions calling for 75w90 can probably thrive on 50w synthetic oil. Using Muscle Products MT-10 may facilitate even lighter oils (see below).
Additives
There are engine oil additive products that contain PTFE (Slick50 for example) made by DuPont. According to DuPont: NEVER use PTFE based oils or additives in an engine oil application. It will clog lifters and cause catastrophic engine failure. PTFE is not soluble in oil and therefore cannot remain suspended. However, it makes an excellent additive for bearing grease and other non-engine lubricants (again, Slick50 products). Categorically, engine oil additives typically fall into just a few categories: they add more of the additives the oil companies are already putting in the oil, they try to make the oil slipperier (PTFE, boron), and “other”.
For the most part, the vast majority of oil additives are a total waste of money. There is no return on investment, the engine doesn’t last any longer, and you don’t get any better fuel economy. However, there are a select few notable exceptions. In the “add more of what the oil companies are already putting in there” category, there really are no good ones. The one exception is a zinc oxide additive for older engines, since the new SN rating removed it.
The slipperier category is a mixed bag. On one hand, you want slippery oil feeding the crankshaft, camshaft, oil pump, lifters, and most other engine parts. However, if the oil is too slippery, the piston rings just slide up the cylinder walls without sealing. Blow-by gasses increase, reducing combustion chamber pressures, and increasing crankcase pressures (definitely not a desirable outcome). Some companies claim their slippery additive is able to determine when to be slippery and when to let the rings seat properly. Two common ingredients in these additives (other than PTFE) are boron/boric acid, and chlorine.
Under the “other” category is Muscle Products MT-10 additives. It’s not an additive package with more of what the oil companies are already using, and it doesn’t make the oil slipperier. In fact, they boast that their MT-10 is NOT A FRICTION MODIFIER. What is it, then?!?
MT-10 is an electrolyte. The zinc bars used on the hull of a ship electrically discourage electrons from forming rust. Technically you could call zinc a catalyst, but in a different context, it could also be called a solid electrolyte. Back to MT-10, if you look at a freshly machined crankshaft journal, it looks so smooth you could use it to shave (or apply make-up). However, under a microscope, there are rips, tears, and gouges in the metal created by the machining process. Muscle Products has electron microscope images of a freshly machined crank journal, then the same journal after 10k miles with their MT-10 additive. The 10k image looks better and smoother than the freshly machined one. Essentially, the engine is “healing itself” by running. On the freshly machined surface, the high peaks are positively charged in relation to the low valleys. Running the engine with MT-10 allows the positive peaks to transition to the negative valleys, to electrically neutralize and smooth the surface. This reduces parasitic losses caused by friction.
MT-10 can be added to the engine oil, transmission fluid — manual and automatic, power steering fluid, differential oil (even with clutch-pack posi units as it is not a friction modifier), and the air conditioning system. They offer special greases for wheel bearings and steering components. They have their equivalent of WD-40 and PB-Blaster. (Though not related, they also offer fishing reel, gun/firearms, and air tool oils.)
I have heard some compelling testimonials for another product called Snake Oil. This product was developed by the late Ron “The Gadgetman” Hatton. The active ingredient has been used in industrial and even aerospace applications for decades. Ron was the first to apply it to automotive lubes. When Ron passed, Tracey Gallaway was donned the new Gadgetman. He tells me that with close to a decade of field use, there has never been a catastrophic failure from the use of Snake Oil. He says virtually everyone sees an improvement in performance, fuel economy, and often quieter drivetrain. It is available at www.SnakeOil.wtf.
By no means am I an expert that has extensively tested everything on the market. If you find something that works for you, use it.
Filters
Years ago, there was an independent study conducted, testing the effectiveness of different oil filters. Surprisingly, the Fram brand filters ranked down with generic offerings as not very effective. At the top of the list was Wix followed by Purolator. Of course, this group didn’t test every single brand available world-wide.
I remember back in the 1970’s it was recommended you change your oil every 3 months or 3000 miles, whichever came first. Even with such short intervals, the oil came out black. On today’s engines, using a high-quality oil and filter, oil changes can comfortably be paced every 7500 - 15k miles (or longer). Considering the high cost of vehicle or engine replacement (there are no more $500 daily drivers showing up on Craigslist), it makes sense to spend just a little more for high quality oil and filters. A vehicle will probably have an oil, transmission, air, fuel, and maybe HVAC filter. Considering how infrequently transmissions need maintained, it makes sense to use only the highest quality oil and filters when they are serviced. The slightly higher cost for better materials is amortized over at least 50k miles.
Bypass filters are canisters with what looks like a roll of toilet paper for a filter element. They are installed in parallel with the stock oil system. They tap small amounts of oil at the oil sender using a “T”, filter that oil, then dump it directly back to the oil pan (maybe through the valve cover or somewhere else convenient). Bypass filters are able to remove solid particles 1/100 the size the normal filter can catch. They are restrictive, which is why they cannot be used as a primary filter. Amsoil uses a bypass filter as part of their 50k mile oil change program. You replace the bypass filter every 10k miles and top off the oil level. Then at 50k you perform a complete oil and filter change. You do not want to use regular toilet paper for the filter element, use only the recommended filter. I can also tell you from experience you don’t want to use the filters as toilet paper.
If you are wanting to improve fuel economy, reduce maintenance costs, or just improve reliability, there is a daunting field of science available (thanks to the internet) to educate you on what works, what doesn’t, and what level of improvement you can expect from what chemistries. This post cannot possibly reflect the latest most up-to-datest offerings available today. Just be aware that modern chemistry can benefit you through better lubricants and additives. (Also see our Additives video.)
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MPGenie Basics 051 Training - Line on Lubricants Part 1
MPGenie Basics 051 Training - Line on Lubricants Part 2
