How many miles on synthetic motor oil?
How many miles on synthetic motor oil?
(OP)
My research indicates that your common gasoline engine can be driven about 12,000 miles between oil changes before contaminates become a concern for induced wear. Some feel a filter change half way is a good idea. Any experiences with extend synthetic oil change intervals?





RE: How many miles on synthetic motor oil?
www.amsoil.com
I always thought that the life of the detergent package was more critical to oil life than amount of contaminates.
Nick
I love materials science!
RE: How many miles on synthetic motor oil?
RE: How many miles on synthetic motor oil?
RE: How many miles on synthetic motor oil?
RE: How many miles on synthetic motor oil?
This has already been extensively covered. Try a site search.
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RE: How many miles on synthetic motor oil?
Lots of oil heads like to change their filters frequently, but usually don't have more than supposition that it's failing- or just a 'good idea'- to justify it.
RE: How many miles on synthetic motor oil?
I change filters every time I change oil.
I try to use filters without a bypass.
I did run good synthetics at double the recommended change interval, however with current change to longer OEM recommended change intervals and OEM specified synthetic oils in some cases, I am now less inclined to extend oil change interval past 10,000 kilometres.
The factor that limits oil life in most cases is Total Base Number (TBN), or the ability to resist exposure to blow by gasses without the oil turning acid.
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RE: How many miles on synthetic motor oil?
in the morning, simply count how long it takes to the light go off for oil.
on my car (audi 90 1995 2.8 V6 189K miles) it takes no more that 1 sec to go off. on fresh oil. but when its is old it takes up to 3 seconds to go off.
and please dont reliai on these numbers, each engine is diferent, as well each woman is diferent. I give no more that 7000 miles. if oil goes black then simply change, what is gona hurt 45 buks, or 30 if you change your self.
I dont care about how long can I go, I care how should I care!!!
RE: How many miles on synthetic motor oil?
RE: How many miles on synthetic motor oil?
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RE: How many miles on synthetic motor oil?
City driving also frequently never lets the engine reach full operating temperature long enough to help rid the oil of condensates. It also tends to see more full rich warm up time that helps dirty the oil.
RE: How many miles on synthetic motor oil?
RE: How many miles on synthetic motor oil?
You need both, but you don't need much water.
More than enough water is also contained in the blow by along with the acid forming gasses.
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RE: How many miles on synthetic motor oil?
All I can do with that is smile...
In addition to increasing acid levels you have a steadily decreasing level of additives...antifoam, dispersants, ZDDP and whatever... lowering the ability of the lubricant to handle high temp and high loading.
Not changing the filter??? Your going to spend ~$30 (in some cases much more) on a quality synthetic oil and cheap out on a $5 oil filter?
Rod
RE: How many miles on synthetic motor oil?
RE: How many miles on synthetic motor oil?
Re read the post, I did not say anything about 'cheap filters'...I did refer to the 'cheap' individual that would change the oil without changing the filter, too! I buy my oil and filters wholesale, by the case...don't know exactly how much the are individually...it matters not as I won't use any other brand, anyway.
Rod
RE: How many miles on synthetic motor oil?
I've heard good things about Wix as well, though don't think I've ever seen one in person. I only worry about my single car so buying by the case is sort of an exercise in predicting how long I will own the car. I bought 6 at once a couple years ago--I think I have one or two left, which is going on my car this weekend more likely than not.
RE: How many miles on synthetic motor oil?
RE: How many miles on synthetic motor oil?
Most lawn mowers are air cooled- making them severe for oil contamination- and run at constant speed, making them mild for wear debris. So it may be the filter can take 100 hrs but the oil can't. What mistake did the Toro engineers make with their recommendation?
RE: How many miles on synthetic motor oil?
Cannot address statements about Toro or the "fact" that oil filters get better with use (??? of course it gets "better" to the point it "filters" 100%!)...I can say that I change filters with oil changes every time and cut my filters open to inspect them, just in case. Just for drill, cut open a few propriety brands and compare...you will be astounded at what you are relying on to "protect" your investments.
Rod
RE: How many miles on synthetic motor oil?
RE: How many miles on synthetic motor oil?
From my post 31/03/06
The problem is that you can't predict when it will become restrictive enough to cause the bypass valve to open occasionally, allowing some previously filtered larger particles that have settled in the bottom of the filter canister to enter the main gallery.
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RE: How many miles on synthetic motor oil?
Not all filters are equal (doh). A high flow racing filter such as a Fram HP-1 has a working DP of around 1 to 2 psi as used on one of my Lotus twincam engines @ ~85psi working pressure in a properly designed race engine oiling system , CLEAN. Dirty, after several race weekends, ~5psi, the point of change in that cars owners regimen. We tried a proprietary filter of ~10 micron capability...DP STARTED at 5 psi! I am not sure of the Fram HP-1, but the equivelent Wix (51515R) that I use is ~40+ micron.
A note, that car was not mine as I still prefer to change oil and filter at no greater than two race weekends, regardless of the DP...(actually I don't even have an extra guage on MY race car).
Rod
RE: How many miles on synthetic motor oil?
The only bad part from synthetics is they degrade very fast where as conventional petrol oils lose properties gradually and predictably. I have some info on it around here somewhere. Basically syth’s are better until they hit high temperature. Temperature will make the properties drop off the chart. Conventional oils recover much better from this and slowly degrade over time. I have also ‘heard’ companies like CAT, do not push synthetics even though they sell it. Cat seems to know of other issues with synthetics over conventional oils. I am not sure if it has to due with emissions or durability.
RE: How many miles on synthetic motor oil?
Your comments re thermal stability of synthetics is exactly opposite all data I have read, and contradicts my first hand experience where synthetic oils have specifically solved problems where overheated mineral oil was causing bearing failures.
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