Oil Change

[DonSor]

With the synthetics and semi-synthetics, I've read that some cars don't have to change oil until 10-15K miles. What happens to the performance of the oil filter then? Since oil filters are full flow filters, if they do their job they should start clogging up way befoe then. Certainly there must be decrease in oil flow come near those mileage. I'm sticking to my 3-4K interval.

Also, what brand oil or additive has MoS2 (Moly Disulfide)?

[timf818]

I'm new here but I have a 2003 Ranger 4x4 and it's full synthetic. I change the oil every 10 thousand miles but I do the filter at 5 thousand miles.
I then top off the oil level with new oil.

[DonSor]

Makes sense changing oil filter at half the mileage of your oil change but what is the cost-effective benefit of using synthetic oil as opposed to standard oil? Most car manufacturers still recommend the same frequency of oil change whether one uses synthetic or not. I can understand (I think) some of the benefits of using syn oils in high performance cars. According to independent reports, there is no better preventive maintenance practice than to change oil and filter as often as 3K miles.

[timf818]

It is to my understanding that the reason for the use of synthetic lube is, that it doesn't lose it's viscosity under the heat like regular oil. Therefor allowing it to last longer and save natural resourcses. I use the synthetics for these reasons. Yes it costs alittle extra but I feel it's worth it because of the lack of varnish and viscosity break down. I have a few friends that change the filter 4 or 5 times before dumping the whole pan. It's up to the user really, I feel the engine is protected better with the synthetic oil.

[yotermanic]

If all we were looking for in an oil was vicosity and lubricating properties, we could filter it and continue using it until it burned up, then we would never have to change the oil and just top it off every thousand miles. Unfortunately, there is a LOT more the lubrication than just the actual petreoleum oil in our motor oil. There are a myrid of anti-friction adn anti-foaming agents in our oil. This stuff is so far removed from the stuff they refine straight out of the ground, it's not funny.

The additives are what you need to truly worry about breaking down. As a rule, though, the additives in synthetics are usually the same as the additives in conventional oil, but they put a WHOLE BUNCH more in. When deciding on a maintenance schedule, you need to do what I do with my heavy trucks. Look at the conditions you drive under, then assess how frequently you need to change the oil. If you plan to keep the car a long time, you may send a couple oil samples off for testing. I good lab can tell you if you have life left in your additives and how much the actual petroleum oil has degraded between the last intervals. In the trucking industry where and oil change can run a couple hundred dollars, this is vital information. The testing's cheap, to. We have an account but I believe I only pay $30 a truck.

Sorry to rant, but I keep seeing "I went to synthetic so I now change my oil every 150 million miles." And it just irritates me to no end that everyone is always convinced that synthetic is a permanant solution to oil changes. I have several applications in my fleet where synthetic oil offers absolutely no advantage over conventional oil because the heat and pressure is extreme enough that the additives break down WAY before the base oil.

In closing, the absolute best thing you can do to ensure that your car is getting the lubrication maintenance it needs is to assess your driving style and follow the manufacturer's reccommended intervals and procedures. I know it's hard for the internet einsteins to keep their mouths shut, but the manufacturer has spent MILLIONS researching this stuff and really, really know what they're talking about. Unless you're willing to go through the time and expense to get oil samples, have them anaylyzed and learn what those results mean, you are best to just do what the owner's manual tells you.

['97ventureowner]

Excellent discussion so far. Very good points have been presented on the argument of synthetic versus conventional. A couple of years back I switched many of my vehicles to Mobil 1 . My driving habits are basically a 60 - 40 mix of highway/suburban driving, so I leave my synthetic in for roughly a year or 12,000 miles , whichever comes first. About halfway through I also change my oil filter and top off any oil lost during the filter change. Some of the benefits to using synthetics are an increased change interval, allowing people to use less oil overall. Using less oil means less dependence on foreign oil, and a decrease in the amount of oil that neeeds to be disposed of/recycles which is good for the environment. Those along with improved lubricating qualities are some good reasons to switch among others.
Make sure, though, you use a good quality filter as there are a lot of sub-par filters on the market that don't do a real good job of filtering your oil. A study was done awhile ago, and updated last year noting some good filters on the market today. That study can be found here: http://minimopar.knizefamily.net/oilfilterstudy.html
If you use conventional oil also make note, as was mentioned in previous posts to follow manufacturer's recommendations for change intervals. Most are not 3000 miles but 5000 miles and up. The 3000 mile oil change pretty much was a marketing tactic among the quick change industry to promote more business for themselves and a higher profit. Oil technology has greatly improved over the last decade or two and they are able to go longer distances between changes.
It was also mentioned in an earlier post that manufacturers recommend the same interval whether it's synthetic or not. It is my understanding that they assume the vehicle owner will be using conventional oil so that's what they make their recommendations on. In the coming years, I believe we will start seeing a breakdown in our owners manuals as to which oils and what the change intervals should be.
Overall using synthetics, although more expensive can end up saving money in the long run as the interval change is longer so we change the oil less frequently and the improved qualities are better for most engines. Still if using conventional then follow your owners manual and use a good quality filter either way.