Ever look at all the motor oil on the shelf and wonder what the numbers mean or what all the differences are?
Well here are some answers.
First….viscosity. Viscosity is a measurement of flow. In this case, how fast the oil will flow at 100 degrees Centigrade. Sometimes this term is translated to thick. How thick the oil is. A crude but usable definition.
So the 2nd number in any motor oil is the viscosity of the oil. A 5W20 oil is thinner than a 5w30 oil.
Why this is important is the engines are designed to have a certain amount of flow at certain temperatures. If too thick an oil is used then your gas mileage will suffer (thicker is harder to push), and the oil will not last as long as it should.
If the oil is too thin it may not pick up enough heat as it courses through your engine and the oil pressure may drop below what the engine needs.
The 1st number is a measurement of the oil’s pumpability at cold tempuratures. In other words a 10w30 will not be any good at temperatures below -20 degrees Fahrenheit. A 5w-30 oil will be fine down to about -30 degrees Fahrenheit and 0w-30 can go all the way to -40 degrees Fahrenheit. Of course out here in New Mexico we rarely go below 0 degrees so it really does not matter that much here.
Now that we have covered viscosity and pumpability let’s talk about those two little letter to the right of the api viscosity indicator.
Modern gasoline engines require different additive packages than modern diesel oils. To that end the first letter (in this case an “S” is for gasoline. Oil designed for diesel applications begin with a “C“.
The second letter is for whatever year range the oil is designed for. For instance an SA oil is an oil designed for a gasoline engine built in the 1920s. Try to put this oil in your 2012 whatever and the engine will not be long for this world.
Today’s rating is now “M“. So a motor oil sold on the shelf today for gasoline engines, should have a rating of “SM“. If you find an oil for sale that has a SL rating it was designed for cars a few years ago. Now modern oils are perfectly fine for older applications. No problems there.
So what kind of oil and viscosity do you need?
That answer is specific to the manufacturer that created your car. I can tell you that most vehicles on the road today use a 30 weight oil. Either 10w30 or 5w30 depending on how cold it gets.
Some vehicles require a thinner oil. Many Fords and Hondas especially need 5w20 oils. Usually the viscosity requirement is on the oil fill cap under the hood. If not there find it in the owners manual or call us. We can tell you.
Very few vehicles on the market today require synthetic oil but a few do. Mostly your higher end sports cars and/or European cars. If your vehicles manufacturer requires synthetic oil I would high recommend you follow that. True, you could put cheaper dino oil in it but by 80 or 90k miles the engine will be sludged up and worn out.
To sum up … the 1st number is an indicator of pumpability at cold tempuratures. The 2nd number is the oils viscosity or how well it flows at 100 degrees centigrade. Hope this helps. We will be talking about other factors in choosing an oil or oil change service all month so stay tuned.
This saying got started in the 70’s, near as I can tell, and has really gotten traction lately. It also feeds right into the OEMs (Original Equipment Manufacturers) wishes which are for you to buy a car every 3-5 years.
Now my rants always slant more toward finding a vehicle you like and keeping it forever. I do not like buying cars every few years because I loathe payments. Sure I like the latest widgets and styles but paying $40k for a car or more is abhorrent to me. If this is not you, and you really enjoy trading out every few years then stop reading this.
If, however, you would like to see your money go for other things than to banks to pay for your ride, read on.
Modern cars are designed two fold
First, to hide or mask problems so they do not bother you. This gives the illusion of quality. Second, to be disposable. 80 to 100k miles is all the manufacturer really wants you to be able to get. Think about this. If the average person in New Mexico drives 15 to 18k miles per year then in 5 years you will have 80 to 90k miles. Just about when the media is saying you need a new car.
It has been my experience, with several personal vehicles, that 300-500k miles is really achievable. And relatively easily as well.
Now, let’s talk about not fixing what ain’t broke.
Remember earlier I said that modern cars are designed to mask problems so they do not bother you. They achieve this with sensors and computers. If one part is weak four other parts pick up the slack. That way you are kept unaware of any issues until they are so expensive to repair that buying another car becomes a real option.
Here are some examples of how manufacturers are building non maintainable cars
- Cars with nonserviceable fuel filters. You never have to change the $50 to $75 filter but rather the $800 – $1000 fuel pump.
- Cars with 90k mile rated spark plugs instead of 30k miles. Only gig is they bury the spark plugs under the intake manifold so the tune up is more expensive than ever before. Of course if you ignore this service the car gets increasingly less fuel economy, less horsepower and the catalytic converter gets stressed, the coils get stressed, the interior of the motor gets gunked up and if you own an engine like the Ford 5.4 liter the plugs actually weld themselves into the head. Good luck getting that to run right ever again.
- Some brakes being manufactured no longer come with squeakers so you cannot tell when they are low and you end up grinding the rotors thereby doubling the cost of the brake job.
- What about lifetime fill transmissions? What a joke. Whose lifetime. Certainly not the car’s. Some cars are now being built without transmission dipsticks or any way to check or service the transmission at all. Again, when (not if) the transmission fails it is perceived cheaper to just buy another car.
- Maintenance free batteries. Again what a joke. This is what the whole automotive industry is going to though. These batteries are maintenance free not because they are better but because the manufacturer sealed the battery. Now you have to replace it instead of service it.
Many folks think that modern car diagnostics should be a snap. Just hook up a code reader to the port under the steering wheel and it tells you which part to replace to fix the car.
That’s it right? Even a monkey could do it. What is the big deal?
I am sorry to report that nothing could be further from the truth. The reality is that modern internal combustion engines are a marvel of computer engineering and thermodynamic and hydrodynamic wizardry. There are usually computers on board just to control the fuel injection. Computers exist for the body control, power train control, HVAC, security and so much more. Feeding information to those computers are modules and under those modules are the actual sensors. Now to make it even more complicated you could have malfunctioning sensors, other modules in the system that are feeding bad information to the sensor reporting the code and failed parts that are linked to other systems, broken wires, melted relays, and a myriad of other problems that can just confound diagnostics. There are even soft codes and hard codes. A soft code is something the computer has only seen once or twice. In other words it is an intermittent problem. A hard code is something that the computer sees consistently.
Not all codes refer to a single part. Codes such as the famous P0300 Random Misfire Code are the bane of diagnosticians everywhere. The P0420 Catalytic Converter Below Threshold Efficiency can be caused by bad gas or bad Oxygen Sensors or a bad Catalytic Converter.
Yes the On Board Diagnostic System, which is usually referred to as OBDII, provides a wealth of information that any seasoned diagnostician needs. At the same time there is an old saying that goes,
“Drink deeply from the well of knowledge or drink ye not at all”
This means that a little knowledge can be a dangerous thing. These parts houses that pull codes for free and then sell you parts based on those codes are quite often diagnosing problems incorrectly. Parts houses sell parts. Repair facilities repair cars. And any reputable repair facility will pull the codes for you free of charge. And then, if possible, help you interpret what they mean.
If the code gives the technician enough information to diagnose then we are home free. An example would be the Gross Evaporative Leak Detected code. Usually means a loose or worn gas cap. Quite often the code simply tells the technician where to begin looking. In that case, paying the doctor to make the correct diagnosis can save a lot of wallet pain before he/she starts performing surgery on your car.
I am only writing about this to help correct some commonly held misconceptions that are costing people more money and time than they usually have. Beware of laymen diagnosing your car. Skilled technicians spend 10s of thousands of dollars and years learning how all those electronics work and even more than that on the tools of the trade. Charlatans offer help without the knowledge to give it.
There are a surprising number of small, inexpensive parts that can lead to expensive engine damage when they fail. It doesn’t seem right.
Fortunately a lot of those things can be taken care of in routine maintenance. They may not be easy to remember, because it is a long list, but your service center can help you know what’s scheduled to be taken care of.
Some of us in Albuquerque New Mexico really don’t look forward to going in for an oil change and then getting a list of the other things the manufacturer recommends or get noticed during the inspection.
But automotive maintenance is all about prevention, and addressing small problems before they get big.
Let’s take the fuel filter for example.
You may not know this but the median age for private vehicles on our Albuquerque New Mexico roads is over nine years. When cars get older, five years or so, they’ve accumulated a lot of dirt and rust in their gas tanks. If that dirt gets into the engine it can cause thousands of dollars worth of damage. So somewhere between that dirty gas tank and the price of a great vacation – is the lowly fuel filter: a very inexpensive part that doesn’t cost too much to replace. And your car will just run better too.
A clogged fuel filter can’t let enough fuel through. You might notice at first that your car is running fine around town, but struggles or sputters on the freeway or when you accelerate. Enough fuel can’t get through to meet the demands of higher speeds. If it gets bad enough your engine might just shut off or not start at all, which could be dangerous.
Some fuel filters have a bypass. When they get clogged, they allow dirty fuel to move around the filter element so dirt ends up in the engine. We’ve already talked about how expensive that can be. Fuel filters without the bypass slow the rate of fuel delivery to the engine so the car’s computer is always calling for more gas. This makes your fuel pump work harder, wearing it out faster. On some vehicles, a new fuel pump can be as much as $1000.
The fuel filter is even very important for newer cars. The fuel is still dirty even if there isn’t rust in the tank. It’s just that the fuel filter will need to be changed more frequently as the vehicle gets older.
How often should you change your fuel filter? Check your owner’s manual. Your service advisor can tell you as well. It’s usually around thirty thousand miles or so. Ask if it’s time for a full fuel system cleaning as well. They often go hand in hand.
It’s good to know that your service center has your back. When you’re motivated to maintain your vehicle’s performance and to reduce operating costs, you’ll think of service center as your ally.
There is a new recall out for the 2009 Cadillac SRX. I suspect that this recall more than likely affects all Cadillac models with the 3.6 L V-6 engines.
One thing that is interesting about this Cadillac recall (#10287) is that the recall itself boils down to a software update for the engine control module. Cadillac states the reason for this upgrade is to prevent excessive wear on the timing chain. How often can you connect software with hard engine parts wearing out?
To clarify the upgrade forces the engine control module to recommend more frequent oil changes.
Here is a quote from the recall notice that was sent:
We have determined that under certain driving conditions, and with extended oil change intervals, the timing chain could wear prematurely and cause the illumination of the service engine soon light. Timing chain wear can be affected by the age of the engine oil and driving conditions.
Here is another quote from the letter that was sent that covers what they will do in the recall:
To ensure your vehicle will not experience this condition, your Cadillac dealer will change the calibration of the engine control module, including the engine oil life monitor, which in most cases will recommend more frequent oil changes.
Now I have, in the recent past, been on my soap box about the original manufacturers recommending service intervals based on selling you a new car every so many years. Not on what is best for taking care of your investment. Here is a prime example of that.
GM (parent company of Cadillac) is one of the worst offenders of this with their oil life monitoring system. The system does not monitor the condition of the oil rather the conditions present in the engine that cause oil oxidation. Yet it is not uncommon for these systems to not recommend oil changes for 10k miles or even more. Clearly longer than the oil manufacturers ever intended.
I do not care what the system monitors; the API sets the limits for oil life not the manufacturers! And those limits are based on chemistry and physical tolerances of the oil not marketing.
If you want to reduce damage to your engine and increase its lifespan change your oil every 3k miles no matter your owner’s manual or the computer on the car says. If you use an oil additive like BG MOA (you get this with every oil change with us without even having to ask) you can go 5k miles with no problem.
If you use a high quality synthetic (Not Mobil 1) you can, at times, go as far as 10k or 15k miles between oil changes. Just be careful here. The oil may be able to go that far but can the filter or the rest of the car? An inexpensive brake reline at 5k can turn into a real nightmare 10k miles later. If you insist on extended drain intervals using a high quality synthetic, simply have the balance of the car inspected every 5k. Every third time, change the oil.
Bottom line, if you want to keep your vehicle alive and relatively cheap to own, have it inspected and serviced every 3k miles to catch problems when they are small.
Here is something that has plagued me over the past couple of years. I had a 2007 Ford Taurus that got itself towed to my shop. The complaint was that the engine started fine but the transmission would not budge from Park. No check engine lights and no problems were evident before this suddenly happened. Very frustrating.
Turns out the brake lights were dead. Specifically, it was a brake light fuse that was unpowering the brake pedal switch. Ever try to shift from Park without stepping on the brake first. Won’t go, right?
It seems that there is a switch on your brake pedal that, if there is no power to it, the system locks your transmission in park but only after you finish driving and place the transmission in Park. Safety, safety, safety.
Safety Can Cause Trouble
It can be a real nightmare to figure out if you are not familiar with these systems. It would make sense that if the gear shifter will not move from Park that the problem is in the transmission and not in the brake system. Right?
Another complication to this is that the dealership did not know about this either. At least they did not tell my customer. She had her vehicle towed there and they charged her $100 or so for a diagnostic and told her that she had a bad transmission. Since the vehicle had 55,000 miles on it at the time there was no more factory warranty so she would have to pay for it.
Thankfully she had a second opinion before replacing the transmission.
After all, when the dealership finished replacing her transmission and the car did the same thing they would have been forced to look further. After replacing a $.50 cent fuse they could have continued to charge her for the new transmission and save face.
The point is that vehicle diagnostics are not as simple as they once were. Everything is interconnected now and snap, knee jerk diagnostics are not very accurate anymore.
When searching for a shop to do your car maintenance and repair, find a shop that spends the time and the money to get the training necessary on your vehicle. How do you this?
You ask questions.
Try the following:
- Can I see your ASE certificates? (ASE is Automotive Service Excellence. While this is not always an indication of knowledge it is an indication that some-one at least is trying to stay certified. That takes effort and effort is what you want)
- You can tell a great deal based on the cleanliness of the shop and the front office/waiting area. If the shop you are inspecting can not even take the time to clean the front area, imagine the level of care they will take with your car.
- What guarantees do you offer? Most shops should have at least 1 year or 12k miles. This is what the average parts house offers. Anything more than that and the shop itself is putting up their own guarantee. That means that the shop really believes in their work.