During the initial warranty period of my new cars, I am forced into some sort of OCD like compulsion via the new car owners warranty agreement to follow what I know, are arbitrary oil change intervals. I do them when stated, because the car manufacturers are basically holding a gun to my head saying I will do their bidding, or run the risk that if my car engine is not engineered, or built properly they will try to weasel out of fixing my car for free for the minor infraction of missing one small oil change.
After the warranty period though I was free! No longer could anyone make me do something that was against my nature...
It was not uncommon for me to go 30,000 miles without changing the oil. I reveled in the thrill of letting my oil work itself into a nice sludge, and thumbing my nose at the industry, thinking I am much smarter than you people! You can't bullshit a bull shiter!
I reasoned that todays modern engines are engineered so well that they can take the abuse, and still live to see 200,000 miles. After all, anecdotally I had my own research! The Subaru I traded in had 196,000 miles on it when I was done with it!
To be fair, I did blow up two engines before that, but those were flukes! They both had issues before I got them! I was doing reverse donuts in the diesel Volkswagen when it died, and the Chevy spectrum was just poorly designed!
Chevys of the mid to late 80s were garbage anyway! ;)
Since I love conspiracy theories I loved to think about how I was smarter than the evil oil cartels who conspire with the auto manufacturers to have larger and larger profits at car owners expense by hoodwinking foolish weekend mechanics DIYer car owners, and just conscientious car owners into changing their oil more frequently than necessary.
Yep, this modo has served me well until I decided to first start towing my tear drop camper with the Mazda 3, and then later to decide I didn't have the financial strength to trade the Mazda in on a new car when it reached the 200,000 milestone I had previously set.
Suddenly I was very interested in the fluid dynamics of common engine oil.
What color should it be?
Why do I need an oil with a good "detergent package"
What sorts of additives do they add to the oil, and what do they do?
Through asking myself those questions, I came up with some knowledge about engine oils.
Since we live in the age of the internet, I was able to find all of those newly important questions for my new found interest, love, and respect for engine oil.
Once I realized that this really DID effect my pocket book, it was all over, I had to know.
Below is what I have found:
A: Used engine oil color doesn't matter. Mostly. People are often troubled by their new engine oil turning black quickly. They shouldn't be.
The reason engine oil turns black so quickly 95% of the time it mostly due to modern engines oils superior ability to store and suspend harmful contaminants in the oil itself and away from any critical parts.
First, there is a detergent pack to help scrub crude off of the engine parts. The detergents in use today are metallic salts called, Sulfonates, phenates, phosphonates, and salicylates
Common dispersant types include polyisobutenyl succinimides and polyisobutenyl succinic esters
Even though modern oils are so good at first scrubbing off the harmful deposits and then storing them inside the oil, viscosity doesn't change, and the oil does not suffer degradation from this.
So just because an oil is black, does not mean it is bad, or needs changed.
Older oils couldn't do this near as well. What happened was that the contaminants circulated round the engine for a while limiting flow rate, and often collecting in the most inconvenient places in the engine. The oil pump sump intake, the oil journals(tubs that supply oil to all the delicate parts of the engine), the grooves of the crank bearings, piston connecting rod bearings, etc.
Older oils may have looked clear, but that just meant they didn't always pick up all the contaminants and store them in suspension inside the liquid of the oil.
Below is a gummed up, and destroyed piston connecting rod bearing. This is likely from other events
which I will go over, but this serves to show you what I mean.
New connecting rod bearings. Used ones in good shape should be like this. Smooth, with clear ports
B: There are many reasons why shorter trips of say 5 miles are much worse for your car engine, than 50 miles per stretch.
I will go over a few.
On short trips in the car, your engine oil does not get the chance to properly heat up and bake, for lack of a better word for the appropriate time in order to cook all the water moisture out of the oil.
This in turn, leads to one major component of the dreaded ENGINE SLUDGE.. Just like "the blob" it will creep up on you and get you!
What a nice clean engine should be
Now in addition to short trips, or more precisely in conjunction WITH not changing your oil, this can lead to engine sludge.
Engine sludge, can break loose and block oil pump pickups, get embedded in oil journals, stick the piston oil rings into the pistons, etc.
Not changing your oil will most likely lead to every above symptom for two reasons right off the top of my head.
I. If you don't change your oil, that wonderful oil that I said it so superior to the oil of old, will get oversaturated. It will start to thicken and be more like well, sludge...
II. If you are not running your car for long periods of time, a sure fire way to get all of that nasty water vapor out, would be to take the car for a drive to let the oil warm up, and then drain all of that nasty "water logged" oil right out of the engine, and replace it with fresh, loving, clean oil.
III. This fact often goes unmentioned on the car guru sights. If your only running your car for short trips, there are many more engine starts than a car with the same mileage that has racked up the mileage on the highway during long, 100 mile journeys.
This of this. Two cars with 50,000 miles on the odometer. Car A has driven 100 miles a day at 65 miles per hour. 2 engine starts a day, which would be 500 total engine starts. Car B, which has driven for 5 mile hops through the city to the mall, has probably more than 2 starts a day, but well just take two for easy math has 10,000 starts over that 50K miles.
Starting your engine cold, is the worse thing for your engine. Most of the wear and tear happens then in the split second before oil has a chance to flow into the critical places!
C: Modern Synthetic motor oil IS better than old fashioned mineral oil in almost all, if not all respects.
You probably have heard horror stories of people switching form regular mineral based motor oil to synthetic and having all sorts of problems. One main problem that people had was developed oil leaks.
This is true. There were issues. What would happen is mineral oils, would swell engine gaskets, while older style synthetics wouldn't. So in essence your engine gasket would thin(or more precisely, wouldn't swell up to fill all the gaps), and the engines would develope oil leaks.
Not only would you have your nice clean driveway and garage marred by the unsightly look of your car defecating on your nice clean surface, but what would happen is your engine would leak oil, and you would need to add more oil regularly to your car.
If you didn't, your engine would run out of oil, and lock up tighter than the lending of modern banks
Equally as important as the oil running out of your engine into the driveway, your car would then burn oil through the combustion process.
It would start to burn oil because of the valve seals "shrinking up", and not providing a good seal. Oil would leak through your valve seals, into the engine combustion chamber, making your car smoke when you gagged on the throttle, burning more oil, fouling your spark plugs, clogging your catalytic converter, and MOST IMPORTANTLY, making you look like a geek to the other drivers
Never fear though!!
Modern Synthetic motor oil, suffers none of those problems! The evil oil cartel, and motor oil manufacturers have gotten smart!
They now put gasket swelling agents into their synthetic motor oils that keep your engine seals in good shape, even if you decide to switch to the premium synthetic oils.
Now that we have discussed how the evils of synthetics have been eliminated, let me list why modern synthetics are actually superior to standard mineral motor oil.
I. Synthetic motor oils are capable of greater engine contaminant storage. Think of this fluid as a larger tank capable of holding within it, safely away from the critical engine parts anything that would get into the oil, and harm the engine.
This is how you can go longer between oil changes than with standard mineral based motor oil.
II. Synthetics aren't as prone to thicken up under extreme cold temperatures in the winter. That means when you start your engine on that ass freezing cold day, the engine oil will flow better and get to the vital parts quicker than standard oils. They have really good pour point depressants that keep the oil from thickening up when cold by preventing the molecular growth of wax crystals.
III. Synthetic oils are less prone to loose their viscosity or "thin out" at extreme temperatures(extreme driving). keeping your engine parts protected during hard driving.
IV. Synthetics clean your engine better than mineral motor oils. Standard oil tends to varnish the inside of the engine parts. Synthetics do not do this, and from what I read can actually clean the varnish off the engine parts.
D: Those fancy, high mileage oils are more than just hype, and clever marketing to trick you out of your hard earned cash..
I have read a great deal from technical magazine articles, and anecdotally online that Valvaline Maxlife really does work.
It has a great additive pack, that actually does condition old seals, and may in fact stop a small oil leak.
I have read story after story online about this. The process of sealing your engine against oil leaks both from your driveways perspective, and your combustion chambers not burning oil, is worth the extra cost.
UPDATE AFTER FIRST OIL CHANGE: The Valvoline Maxlife completely stopped my car form burning oil. Before that, the car would burn quite a bit of oil. In fact, if I waited a month to change my oil, I would come back, and the oil level wouldn't even read on the dipstick. Now when I check the dipstick, the level hasn't moved!
Most oils have a lower level of the type of additives that are actually in the products above.
Most oils are detergent oil, meaning they have additives that help to scour off crude from your engine parts. Just not to the level of the detergents in high mileage oil.
High mileage oils have special anti-wear additives in them, that are designed to limit metal stress.
Forget about special after market oil additives like Slick 50, and Duralube. There is no scientific evidence they do anything. Just get a good oil, and change it fairly regularly, and your engine will be happy with you!
E: Another important topic that isn't about the oil so much, as the tool used to keep it clean, is your oil filter.
Changing your oil filter is just as important as changing your oil.
There are some writings that you should change it half as often as the oil, and how as the oil filter becomes used it can filter smaller and smaller particles, which makes some sense, but just to be on the safe side, change it at the same time.
Buy a good oil filter, don't cheap out! Especially if you are like me, and like to push the envelope on oil change intervals.
Cheap filters not only will filter less harmful particles like metal particles, but may also become clogged easily.
If your oil filter becomes clogged, you may find your engine starved for oil, and locking up.
I am not sure all oil filters have the bypass valves that are designed to open up when they become saturated and clogged. Especially filters like mine the Mazda which are just an interchangeable paper filters, instead of the normal steel canister.
I will attach links to the persons site that incurred a huge expense to test different brands of oil filters.
I am sure I am missing some stuff. I set out to just record my findings. There are some really knowledgeable people out there that can tell you about oil chemistry, base stock, etc.
I am not claiming to be an expert, this just tries to summarize my findings, and I attempted to write it in a way others can read.
Some of this I knew. I was aware about the short trips, and what engine sludge does to an engine. I knew that they had started adding swelling agents to synthetics some years ago, and how they were previously problems.
However, I didn't know how easily sludge forms even in todays engines, with the oils of today, how the detergents in the oils work so much better than in old days, how the modern engine oils are so good at suspending particles and keeping them away from engine parts, and the fact that High Mileage oils actually do work, and are worth the money...
I have worked on engines(major rebuilds, bottom ends, cams, connecting rod bearings, new pistons, etc) for years, but stupidly never saw the importance of common engine oils. I always thought engine design was the most important, and still think it is, but engine oil, is half the battle.
Feel free to let me know if I need corrections!
As well as this...