Another great article from @Texas1911. #oilchange #changeyouroil #intervals
For many car owners there’s a big misconception about oil change intervals. I will explain how to use your own logic to infer a proper oil change interval as well as debunk some of the myths surrounding when to change your oil. I will also discuss some of the differences between grades of oil, particularly synthetic versus conventional oil, and how they apply to oil changes. Lastly, I will talk about seasonality and when to short-change oil.
TL
R – Give me the Cliff Notes!
While some specific cars recommend very long intervals, this is not a great idea without a very high quality oil and monitoring. The $100 you spend doing a shorter interval is good insurance for avoiding issues and keeping fresh, clean oil in the engine. Typically the filter should be changed regularly, even if you are not changing the oil itself. This will insure you will get the maximum life out of both the engine and oil.
What does Motor Oil do?
Most people believe that motor oil is there to lubricate all the parts within the engine, but in reality motor oil does considerably more than that to keep your engine running. Here’s a list of what motor oil does in order of importance.
Separates Metal Components
Oil is pumped through the engine at a high pressure by the oil pump. This oil follows small passages throughout the engine called oil galleys. These paths lead to critical points in the engine like the crankshaft, rod bearings, camshaft(s), and even the turbocharger if your engine has one. Each of these components needs to float on a very thin layer of oil in order to avoid wear and rapid engine failure. This oil boundary layer is forced between the bearings (small sacrificial pieces of soft metal) by the oil pump’s pressure. This is the most important function of the oil. Without this layer, the engine would fail in seconds.
Cools Engine Parts
We now know that oil flows throughout the engine. It also gets flung all over the insides of the engine by the crankshaft spinning at very high speeds. From there it pulls heat from the various objects that it comes in contact with, namely the cylinder walls, pistons, crankshaft, and multiple bearing surfaces. Without this, internal parts would continuously heat up and expand. This expansion would force the important oil layer out, or cook off the oil, which would lead to engine failure.
Lubricates Rotating Assembly
The primary source of lubrication is the fact that the metal parts don’t touch each other. However, the oil itself and the additives in the oil help to reduce internal friction even further. The benefit is a cooler, longer lasting, and more fuel efficient engine.
Why do you Need to Change your Motor Oil?
Oil wears out, or should I say, oil loses it’s abilities to perform at it’s peak due to a number of reasons. Typically these reasons are as follows.
Excessive Heat
While your oil temperature might hover around the 210 – 225? F mark, internally the oil will reach much higher temperatures. This can cause burn-off, coking (ashing), and other failures of the oil including a loss of oil pressure due to too low of a viscosity in extreme situations. This build-up of burnt oil can clog oil passages and cause further problems.
Synthetic oil is less susceptible to thermal stress as it was designed to handle it.
Viscosity Shift
Modern oils feature a viscosity range depending on the temperature of the oil. This is ideal because during a cold start-up you want the oil to be non-viscous, but at high temperatures you want it to retain some viscosity to promote pressure at bearing surfaces. This is why you see oil weights like, 10w30 or 0w20. The oil achieves this from it’s viscosity-index modifier additive. Over time, however, the immense shear load at the bearings causes this additive to degrade along with loss due to chemical reactions. This causes the oil to shift in it’s viscosity, which affects oil pressure, flow, and other properties negatively.
Synthetic oil does not rely on these additives as much, and will exhibit less shift.
Contaminants
Oil actively cleans the internal components of the engine. Part of the additive package, particularly in diesel oils, is a detergent. Oil seeks to trap contaminants and pull them away from the components and deposit them into the oil filter, or dilute them into the total oil volume. Some examples of these contaminants are fuel, ash, carbon, water, and glycol (coolant).
Oil temps are almost always regulated above 212? F to boil off any water vapor, but excessive idling in a cool environment can quickly attract moisture. Water is particularly bad because it degrades the oil and ionizes any acids which causes corrosion. Fuel will dilute the oil and cause it to lose a significant amount of it’s viscosity index. As an example, a diluted oil might go from a 15w40 to a 10w30.
Exhausted Additives Package
Oil lives in a very harsh environment and is asked to do a lot. To help the base stock oil companies will add a proprietary package of additives. These can include zinc dialkyl dithiophosphate (ZDDP), molybdenum disulphide, viscosity-index modifiers, seal conditioners, anti-foam, and other additives. Over time, these additives react with either contaminants or the engine parts themselves which reduces the oils ability to perform.
Common Oil Change Interval Myths and Misunderstandings
The 3000 Mile Oil Change
There is no reason to change the oil at 3000 miles for 99% of the motor vehicles on the road.
That being said, the only danger of short-changing the oil at 3000 miles is that you will just be wasting money and time. It will not harm your engine in the least. If it’s what you know and trust, and you want to throw money away for peace of mind, then keep on doing what you’re doing.
Oil change intervals depend on the engine operating conditions (load, temp, etc.) along with oil volume and oil filter capacity. What works for a 2011 Toyota Camry will not work for a 1988 Porsche 911.
The 15000 Mile Oil Change
It’s just not worth the “savings” to run this long on oil, in my honest opinion. Unless you’ve specifically tested the oil and monitored it for the duration of the interval it’s questionable if you’re not actually causing harm. There are some vehicles that are specified to run for long intervals and some oil manufacturers build their oil to handle long intervals. In the first case, the oil filter will also be sized to handle the large amount of contaminants, but in the second case, you’ll be looking to replace the oil filter regularly to properly run the oil for that length.
Unless you are managing a fleet of vehicles or just really eaten up with long change cycles, I’d recommend sticking to a more frequent change cycle.
My Car isn’t Designed for Synthetic! It’s OLD!
This is an old mechanics tale. Synthetic oil will work in any engine that conventional oil will work in. It has better properties than conventional oil, so in fact, your engine will probably thank you for stepping into the modern age, after all … synthetic oils have been around for over 50 years.
Synthetic Oil makes Oil Leaks get WORSE!
This is hard to say one way or another. Synthetic oil does have the same additives to improve the conditions of the engine’s seals, but it does have superior low temperature flow properties. The latter can work against you, but frankly if your engine is hemorrhaging oil you need to replace your seals, not put sub-par oil in your engine. (That’s easier to type than dropping a 250# transmission in your driveway to pull a $11 seal, but such is the luxury of writing, ha!)
When to Change your Motor Oil
The best starting point is in your Owner’s Manual. It will not only outline the oil change interval but the type and quality of oil you need. Engines are designed with a specific weight and type of oil. This is not exactly set in stone, but if you are using the engine for daily commuter duty or light towing it is the best guideline for you to go off of. If the interval is long, you can short-change the oil if you choose, but if you follow the long change interval, then you’d be best to follow the regimen exactly.
If you use your car for racing, drive it hard, or do a lot of towing it’s in your best interest to change the oil more often. This environment accelerates oil degradation, and its also an environment that requires a lot of the oil. Protect your engine, or enjoy replacing rod bearings and turbos.
If you live in an extreme environment, which includes both HOT and COLD, it is wise to change your oil more often, or at least, being very strict on the OEM regimen. Summer temperatures constantly above 100? F or winter temperatures consistently below 20? F during the hours you drive your vehicle will also accelerate oil degradation. It is wise to consider a higher viscosity oil for the hot summer months, and a lower viscosity oil for cold-starts in the winter.Author Note / Example: I live in Texas, which see’s very high summer temps for at least half the year. My car runs about 20 PSI of boost pressure, which is hard on the engine and heats the oil quickly. As a result, I will run a higher viscosity oil than specified for my engine in the summer months. My OEM calls for a 5w30 but I run a 10w40. As a result I see similar oil temps but with higher pressure which is important since I have very high cylinder pressure pushing on the bearings.
The more oil your vehicle holds the less often you need to change it. Larger oil volumes typically have more to do with heat capacitance, but a second benefit is that common contaminants dilute the oil slower. This doesn’t mean you should run out and put another quart in your Honda Accord, too much oil is bad in many ways.
Synthetic oil will run for longer in any engine. That’s not to say that conventional oil is not good, or that synthetic is worth it for your particular needs, but a good quality synthetic will be better suited to handling long change intervals.
Original Article: http://www.vikingspeedshop.com/oil-change-interval-change-oil/
For many car owners there’s a big misconception about oil change intervals. I will explain how to use your own logic to infer a proper oil change interval as well as debunk some of the myths surrounding when to change your oil. I will also discuss some of the differences between grades of oil, particularly synthetic versus conventional oil, and how they apply to oil changes. Lastly, I will talk about seasonality and when to short-change oil.
TL
R – Give me the Cliff Notes!- Gasoline Passenger Cars – 5,000 to 7,000 Miles
- Diesel Passenger Cars – 5,000 Miles
- Sports Cars – 5,000 Miles
- Hard Driven / Raced Sports Cars – Very Short, Especially Turbos and High Revving Engines
- Gasoline Trucks (1 Ton or Less) – 7,000 Miles
- Diesel Trucks – 10,000 Miles
While some specific cars recommend very long intervals, this is not a great idea without a very high quality oil and monitoring. The $100 you spend doing a shorter interval is good insurance for avoiding issues and keeping fresh, clean oil in the engine. Typically the filter should be changed regularly, even if you are not changing the oil itself. This will insure you will get the maximum life out of both the engine and oil.
What does Motor Oil do?
Most people believe that motor oil is there to lubricate all the parts within the engine, but in reality motor oil does considerably more than that to keep your engine running. Here’s a list of what motor oil does in order of importance.
- Separates Metal Components
- Cools Engine Parts
- Lubricates Rotating Assembly
Separates Metal Components
Oil is pumped through the engine at a high pressure by the oil pump. This oil follows small passages throughout the engine called oil galleys. These paths lead to critical points in the engine like the crankshaft, rod bearings, camshaft(s), and even the turbocharger if your engine has one. Each of these components needs to float on a very thin layer of oil in order to avoid wear and rapid engine failure. This oil boundary layer is forced between the bearings (small sacrificial pieces of soft metal) by the oil pump’s pressure. This is the most important function of the oil. Without this layer, the engine would fail in seconds.
Cools Engine Parts
We now know that oil flows throughout the engine. It also gets flung all over the insides of the engine by the crankshaft spinning at very high speeds. From there it pulls heat from the various objects that it comes in contact with, namely the cylinder walls, pistons, crankshaft, and multiple bearing surfaces. Without this, internal parts would continuously heat up and expand. This expansion would force the important oil layer out, or cook off the oil, which would lead to engine failure.
Lubricates Rotating Assembly
The primary source of lubrication is the fact that the metal parts don’t touch each other. However, the oil itself and the additives in the oil help to reduce internal friction even further. The benefit is a cooler, longer lasting, and more fuel efficient engine.
Why do you Need to Change your Motor Oil?
Oil wears out, or should I say, oil loses it’s abilities to perform at it’s peak due to a number of reasons. Typically these reasons are as follows.
- Excessive Heat
- Viscosity Shift
- Contaminants
- Exhausted Additives Package
- Peace of Mind
Excessive Heat
While your oil temperature might hover around the 210 – 225? F mark, internally the oil will reach much higher temperatures. This can cause burn-off, coking (ashing), and other failures of the oil including a loss of oil pressure due to too low of a viscosity in extreme situations. This build-up of burnt oil can clog oil passages and cause further problems.
Synthetic oil is less susceptible to thermal stress as it was designed to handle it.
Viscosity Shift
Modern oils feature a viscosity range depending on the temperature of the oil. This is ideal because during a cold start-up you want the oil to be non-viscous, but at high temperatures you want it to retain some viscosity to promote pressure at bearing surfaces. This is why you see oil weights like, 10w30 or 0w20. The oil achieves this from it’s viscosity-index modifier additive. Over time, however, the immense shear load at the bearings causes this additive to degrade along with loss due to chemical reactions. This causes the oil to shift in it’s viscosity, which affects oil pressure, flow, and other properties negatively.
Synthetic oil does not rely on these additives as much, and will exhibit less shift.
Contaminants
Oil actively cleans the internal components of the engine. Part of the additive package, particularly in diesel oils, is a detergent. Oil seeks to trap contaminants and pull them away from the components and deposit them into the oil filter, or dilute them into the total oil volume. Some examples of these contaminants are fuel, ash, carbon, water, and glycol (coolant).
Oil temps are almost always regulated above 212? F to boil off any water vapor, but excessive idling in a cool environment can quickly attract moisture. Water is particularly bad because it degrades the oil and ionizes any acids which causes corrosion. Fuel will dilute the oil and cause it to lose a significant amount of it’s viscosity index. As an example, a diluted oil might go from a 15w40 to a 10w30.
Exhausted Additives Package
Oil lives in a very harsh environment and is asked to do a lot. To help the base stock oil companies will add a proprietary package of additives. These can include zinc dialkyl dithiophosphate (ZDDP), molybdenum disulphide, viscosity-index modifiers, seal conditioners, anti-foam, and other additives. Over time, these additives react with either contaminants or the engine parts themselves which reduces the oils ability to perform.
Common Oil Change Interval Myths and Misunderstandings
The 3000 Mile Oil Change
There is no reason to change the oil at 3000 miles for 99% of the motor vehicles on the road.
That being said, the only danger of short-changing the oil at 3000 miles is that you will just be wasting money and time. It will not harm your engine in the least. If it’s what you know and trust, and you want to throw money away for peace of mind, then keep on doing what you’re doing.
Oil change intervals depend on the engine operating conditions (load, temp, etc.) along with oil volume and oil filter capacity. What works for a 2011 Toyota Camry will not work for a 1988 Porsche 911.
The 15000 Mile Oil Change
It’s just not worth the “savings” to run this long on oil, in my honest opinion. Unless you’ve specifically tested the oil and monitored it for the duration of the interval it’s questionable if you’re not actually causing harm. There are some vehicles that are specified to run for long intervals and some oil manufacturers build their oil to handle long intervals. In the first case, the oil filter will also be sized to handle the large amount of contaminants, but in the second case, you’ll be looking to replace the oil filter regularly to properly run the oil for that length.
Unless you are managing a fleet of vehicles or just really eaten up with long change cycles, I’d recommend sticking to a more frequent change cycle.
My Car isn’t Designed for Synthetic! It’s OLD!
This is an old mechanics tale. Synthetic oil will work in any engine that conventional oil will work in. It has better properties than conventional oil, so in fact, your engine will probably thank you for stepping into the modern age, after all … synthetic oils have been around for over 50 years.
Synthetic Oil makes Oil Leaks get WORSE!
This is hard to say one way or another. Synthetic oil does have the same additives to improve the conditions of the engine’s seals, but it does have superior low temperature flow properties. The latter can work against you, but frankly if your engine is hemorrhaging oil you need to replace your seals, not put sub-par oil in your engine. (That’s easier to type than dropping a 250# transmission in your driveway to pull a $11 seal, but such is the luxury of writing, ha!)
When to Change your Motor Oil
The best starting point is in your Owner’s Manual. It will not only outline the oil change interval but the type and quality of oil you need. Engines are designed with a specific weight and type of oil. This is not exactly set in stone, but if you are using the engine for daily commuter duty or light towing it is the best guideline for you to go off of. If the interval is long, you can short-change the oil if you choose, but if you follow the long change interval, then you’d be best to follow the regimen exactly.
If you use your car for racing, drive it hard, or do a lot of towing it’s in your best interest to change the oil more often. This environment accelerates oil degradation, and its also an environment that requires a lot of the oil. Protect your engine, or enjoy replacing rod bearings and turbos.
If you live in an extreme environment, which includes both HOT and COLD, it is wise to change your oil more often, or at least, being very strict on the OEM regimen. Summer temperatures constantly above 100? F or winter temperatures consistently below 20? F during the hours you drive your vehicle will also accelerate oil degradation. It is wise to consider a higher viscosity oil for the hot summer months, and a lower viscosity oil for cold-starts in the winter.Author Note / Example: I live in Texas, which see’s very high summer temps for at least half the year. My car runs about 20 PSI of boost pressure, which is hard on the engine and heats the oil quickly. As a result, I will run a higher viscosity oil than specified for my engine in the summer months. My OEM calls for a 5w30 but I run a 10w40. As a result I see similar oil temps but with higher pressure which is important since I have very high cylinder pressure pushing on the bearings.
The more oil your vehicle holds the less often you need to change it. Larger oil volumes typically have more to do with heat capacitance, but a second benefit is that common contaminants dilute the oil slower. This doesn’t mean you should run out and put another quart in your Honda Accord, too much oil is bad in many ways.
Synthetic oil will run for longer in any engine. That’s not to say that conventional oil is not good, or that synthetic is worth it for your particular needs, but a good quality synthetic will be better suited to handling long change intervals.
Original Article: http://www.vikingspeedshop.com/oil-change-interval-change-oil/
