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bmxmike
04-25-2007, 12:46 AM
Ok i making this thread cause a few of us are taking over 98ACR thread.

Sludge

The number one reason for oil changes is to prevent the formation of sludge. It's important to understand how sludge forms and how sludge formation is prevented.

How Sludge is Prevented
Additive in the detergent oils 'wash' any contaminant particles off of internal engine parts and hold these particles in suspension until the oil is changed. It's important to understand that these particles are too small to cause engine wear, but they do turn the oil a darker color. The key thing is to change the oil before the oil becomes too saturated with contaminants to hold any more, but color is not an indication of this condition.

How Sludge Forms
As explained above, modern detergent oils suspend contaminants so they do not settle on engine parts and form sludge. When the oil becomes saturated with contaminant particles new particles settle out of the oil onto the internal engine parts and form sludge. This is why it is so critical to perform oil changes before this level of contamination is reached. The only way to know if you're oil needs changing is to have an oil analysis done. Absent this, play it safe and follow the severe service interval specified in the owners manual. Remember that the contaminants come from the combustion process of the gasoline and and the air. Synthetic oil will not prevent these contaminants. Synthetics may be marginally better at suspending more contaminant particles, but not enough to prolong oil changes by much.

Never attempt to clean the inside of your engine with one of those engine flush procedures that many shops try to sell. If you've been diligent about oil changes there will be no sludge. If there is a lot of sludge then the last thing you want to do is to dislodge it all at once.

Oil Change Intervals

People have some many different ideas about when, what miles, oil color, etc.. to change there oil. Really its just personal choice, also driving condition. Here are just a few myths that have gone around

The 3000 Mile Myth
It had a scientific basis when engines used non-multi-weight, non-detergent oil. It no longer has any scientific basis, but it is still being promoted by certain entities, most notably the oil change industry in the United States. This myth is also sometimes known as the "Cheap Insurance Myth."
-------The 3000 Fact.....____________________There are still vehicles that need 3K oil changes, but it's not because the oil goes bad after 3K miles. One example is the Saturn S series. These vehicles have a timing chain system that is very sensitive to clean oil because oil pressure is used as hydraulic fluid to ratchet up the timing chain tensioner. If varnish forms in the timing chain tensioner bore then this system can fail and the chain will become loose and eventually break. Dealers have gone as far as tearing out the normal service schedule (6000 miles) and leaving only the severe service schedule. If your engine is destroyed (under warranty) by a failed timing chain then the dealer will legitimately request evidence of oil changes. Unfortunately this problem usually won't manifest itself during the warranty period.

Dark Oil Myth
Dark oil does not mean that you need a oil change. The way modern detergent motor oil works is that minute particles of soot are suspended in the oil. These minute particles pose no danger to your engine, but they cause the oil to darken. A non-detergent oil would stay clearer than a detergent oil because all the soot would be left on the internal engine parts and would create sludge. If you never changed your oil, eventually the oil would no longer be able to suspend any more particles in the oil and sludge would form. Fortunately, by following the manufacturer's recommended oil change interval, you are changing your oil long before the oil has become saturated. Remember, a good oil should get dirty as it does it's work cleaning out the engine. The dispersant should stop all the gunk from depositing in the oil pan.

Switching From Synthetic Myth-credit to Evil-G-nius
When you are changing your oil, if you have a non-synthetic that you want to use it is ok. What i mean is, That if you have synthetic in your motor now, you can use a non-synthetic without anyproblem!

Breaking in a Engine Myth
It use to be said that when breaking in a engine use a non-synthetic blend. Nowadays this is untrue. One of the myths surrounding synthetic oils is that new engines require a break-in period with conventional oil. The fact is, current engine manufacturing technology does not require this break-in period.

Severe Service versus Normal Service
Each manufacturer specifies what constitutes normal and severe service. Generally, severe service consists of operating the vehicle in a very muddy or dusty areas (because dust particles get through the air filter and contaminate the oil more quickly), operating the vehicle in a very hot areas (heat breaks down oil more quickly), using the vehicle only for short trips in cold weather (the moisture in the oil never gets vaporized), or using the vehicle for towing or when carrying a car-top carrier. You'll often see claims such as "everyone falls into the severe service category," but these claims are untrue (follow the money and see who's making these claims). If you primarily do freeway driving in moderate weather you do not fall into the severe service category. If you're in doubt, the best way to see if you fall into the severe service category is to have an oil analysis done at the mileage of the severe service interval. Many people just like to play it safe and follow the severe service schedule, which is fine, but there is no benefit in changing the oil sooner than the severe service schedule states.

Oil Filter Change Interval
Back in the day it was said to change the Oil filter every other oil change. This was good back in the day of none-detergent motor oil, because the sludge and soot would remain on the engine parts and the filter did not get clogged as much. Nowadays the filter should be changed at every oil change. There are some people who believe so much in synthetic oil that they change filters without changing the oil. There's no harm in changing the filter without changing the oil, but there is no point in doing this.

For those who don't like to Do It Yourself
Quick-Lube (and dealer) Problems to Watch Out For

1. SAE30 oil. Some quick-lube places have been known to offer advertised specials that use SAE 30 oil, as opposed to 5W30 or 10W30. Pay the extra for the proper oil, or better yet avoid merchants that try to pull this kind of thing because it's an indicator that they are less than honest.

2. Trying to use the wrong oil because it's what they have in bulk. Insist on the oil that is specified on your filler cap and in your manual.

3. Pumping the oil out through the dipstick hole instead of removing the drain plug. I came across this gem when I asked if I needed to bring my own copper drain plug gasket. They said that they didn't remove the drain plug to drain the old oil. This was the Oil Changer location at Kifer & Wolfe in Sunnyvale, California. Pumping the oil out through the dipstick hole is a terrible way to get the old oil out because it leaves a lot of junk in the bottom of the oil pan. This was a long time ago and maybe they've changed their ways since then.

4. Selling unneeded and overpriced services such as engine flushes.

5. Selling overpriced, and often low quality, parts such as wiper blades and washer fluid, PCV valves, thermostats, etc. Never let a quick-lube place do any mechanical work on your vehicle.. They do no use journeyman mechanics.

6. Using poor quality filters. You really want to bring your own filter, from the dealer, with you when you go to a quick-lube place. They may take $1 or $2 off the price if you do this but don't count on it.

7. If you have a vehicle that actually still has Zerk fittings to lubricate then be sure that they actually lubricate these fitting. Most cars no longer require lubrication but some trucks still do.

8. Do not let a quick-lube place change or add any fluids other than oil. No transmission fluid, no brake fluid, no power steering fluid, no antifreeze, no oil additives, no fuel additives. It is just too easy for them to use the wrong fluid and cause permanent damage to your vehicle.

Which Oil to choose
When choosing a oil there is no special brand that is better than the rest. Though some oil's may perform better than others.

Detergent Oils
Virtually all modern multi-weight oils are detergent oils. Detergent oil, cleans the soot of the internal engine parts and suspends the soot particles in the oil. The particles are too small to be trapped by the oil filter and stay in the oil until you change it. These particles are what makes the oil turn darker. These tiny particles do not harm your engine. When the oil becomes saturated with soot particles and is unable to suspend any more, the particles remain on the engine parts. Fortunately, with the current oil change intervals the oil is changed long before the oil is saturated.

Non-detergent oil, such as SAE 30, is not used in modern passenger vehicle engines. It is still used in some gasoline engines such as lawnmowers.

5w30 vs. 10w30
Ok this is where many different thoughts come in. Now back in the day there were not many choices in oil weight. Nowadays though, there are many different options to choose from. The main difference is 5w30 will flow better in colder climates. Now here is my give on the two.....

--5W30--
Most newer cars use this type. The main reason is that Bearing space is smaller and this will flow better between it.

--10W30--
Now if you get your oil changed by a shop almost always this is what you will get (unless you take it to a dealership or special shop). The main reason is that "most" older vehicles use this and it is cheaper for them to stock one in bulk than a few different types. This isn't bad as this is basically a Universal oil weight. Now this oil is recommended for older vehicles and ones with engine wear. The main reason is bearing space is greater and provides a better cushion. Also because it leaves a protective film on the cylinder walls on older vehicles.

Just rember this!
Thicker is Better Myth
The reason that oil viscosities have gotten thinner is because bearing clearances have become smaller. Using thicker oils will interfere with oil flow and the oil pressure will increase. In a worn engine it may be okay to increase the viscosity of the oil because the bearing clearances have become larger.[/b]

Synthetic Oil
Advantages of Synthetic
Synthetic oil was originally developed for high performance racing engines. Mobil tried to popularize synthetic oil for passenger vehicles back in the early 1970's. At the time, Mobil was promoting 20K or 25K oil changes with synthetic, but they soon backed down from this. Synthetic oil is a good choice if you have a vehicle with a high performance engine (in fact synthetic is required for many of these engines). It is also a good choice if your vehicle is operated in extremely cold climates. It has higher resistance to breakdown caused by heat and it flows better in extreme cold. Unfortunately for the synthetic oil industry there is virtually no advantage to using synthetic oil in a non-high performance engine that is operated in moderate climates. You probably could go a bit longer between oil changes with a synthetic, i.e. following the normal service schedule even if you fall into the severe service category, but I wouldn't advise this. In short, synthetic may give you the peace of mind of knowing that you are using an oil that is far better than necessary for your vehicle, but it won't reduce wear or extend the life of the engine. The mistake some people make it to wrongly extrapolate these benefits onto normal engines operated in mild climates, with the ultimate lack of any knowledge being manifested with statements such as "synthetics provide 'Peace of Mind,' or 'Cheap Insurance,'" or other such nonsense.

Oil Additives
Now I'm not saying all oil additives are bad, and if your not using a detergent then go ahead. I'm just putting this because I have had some problems with detergents breaking with additives so be careful!

Do not use any oil additives no matter how much they are hyped on TV.
They provide no benefit and can interfere and react with the additives already present in the oil. Some additives have particles that can clog oil passages and clog filters. Common additives that are heavily hyped are Slick 50, Duralube, and Prolong.

Filters

Regular Replacement Filters

Manufacturer Filters
This is usually the best choice for your vehicle.

Aftermarket Filters
These are filters made by companies like Fram,Wix, Motorcraft, Lee, AC/Delco, Bosch, Casite, Hastings, Pennzoil, Valvoline, and Purolator. The quality of these filters varies greatly. In many cases the auto manufacturer uses these filters themselves. Private label filters are made by these companies as well.

Trade Brand Filters
These are filters made for the oil change industry. They are actually no worse than the poorer quality aftermarket filters. You can't buy these at an auto parts store but you'll see them used at many of the quick oil change places.

Premium Filters
Some manufacturers of synthetic oil also make so-called synthetic filters. These are high priced and have not been proven to provide any benefit over a high quality manufacturer of aftermarket unit.

-----------Extras--------------------
Amsoil
Amsoil actually makes some very good products. The negative image of Amsoil is due to their distribution method (MLM) and their marketing approach. If Amsoil products were competitively priced with Mobil 1 and other synthetics, and if I could buy them in a store, I would not hesitate to use their XL-7500 synthetic as opposed to Mobil 1. What upsets me about Amsoil is that they didn't disclose until recently (and then it was by accident) the real reason that their oils (except for XL-7500) are not API certified. In the past they came up with all sorts of bizarre excuses about the reason for their lack of API certification and this greatly contributed to the distrust that people have of the company.

So hopefully this will help some people choose some oil. Post your thoughts or experiences up

evil-G-nius
04-25-2007, 11:21 AM
Pretty good. Another Myth not mentioned...the myth that once you go synthetic you cant go back to conventional oil. It is completely untrue

bmxmike
04-25-2007, 11:42 AM
Ya that is ture. I know a few people i know thought they couldnt after i talked to them...

---im goin to add some stuff and ill add your part Evil-g and ill give you credit

6G72gearhead
04-25-2007, 01:31 PM
Oh and going to synthetic on an old engine is not bad for it, its just if there are any almost leaks, the synthetic will turn them into leaks.