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Synthetic motor oil

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Comments

  • netminderonenetminderone Member Posts: 1
    My truck has 200000 miles on it. I had it since new. The oil is changed every 2-3 thousand miles with 10w-30. I was going to put in synthetic motor oil but I was told that it will ruin my motor because of the mileage. Is this true?? I thought that synthetic oil works better for high-mileage engines. Any suggestions??
  • ruking1ruking1 Member Posts: 19,826
    An important question might be how long /many miles do you plan on keeping it?

    Switching will probably be ok, but why? What would be your expectations?

    It is false that it will ruin your motor.

    It also might be tricky depending on the internal conditions as a result of running conventional oil for 200,000 miles..
  • ralph1970ralph1970 Member Posts: 28
    I always switch over to synthetic oil when I buy a used car or truck. I plan on keeping them on the road as long as possible. I will sell it someday and I hope someone else will do the same.

    You will find that a synthetic oil will do a better job of keeping the engine clean, and after 200K there is probably a lot to clean out. I use an engine flush, cheap oil, and an inexpensive filter to do that.

    I have found that I may get oil leaks after flushing the engine because sludge is what was sealing the oil in the engine. A 1964 I did, I had to drop the pan to replace the gasket and I scraped out about a half inch of sludge. I also had to replace the valve cover gaskets and the front seal.

    I then put in synthetic oil and a bypass oil filter. Before I sold it five years later, without an oil change, I had a oil analysis done and the oil was still good for continued use. (I would not recommend anyone going that long without good filtration.) That was my experience.

    Some others that I switched over the engine flush alone has worked without any problem. The two cars that I'm still driving, a '92 and '73, I just just switched over without a problem. It all depends on the condition of the engine and how it has been maintained.
  • ralph1970ralph1970 Member Posts: 28
    I take it that you others at TDI have a problem with Amsoil. :(

    I know that ExxonMobil is a big supplier of PAO's. It would not be surprised if that is where Amsoil gets theirs. I did not say that it was not high quality base stock. I'm just trying to compare synthetics to be sure I'm using the best for my needs.
  • ruking1ruking1 Member Posts: 19,826
    ..."While I think Amsoil is a top quality oil and there are a few (TDIer's) folks that use it, other specified brands (CJ-4 specification, etc) test better (as measured) than Amsoil, including Shell's Rotella Synthetic, Total Quartz INEO, Mobil One (CJ-4)etc. "...

    ..."I would not be surprised if they buy the PAO group IV basestocks from ....ExxonMobil..... So from that point of view how can it not be of high quality? "...

    YOU: "...I take it that you others at TDI have a problem with Amsoil. "...

    I am not sure where you get that from my above quotes !?

    Currently one of the best bypass filter set ups is the AMSOIL EA xxx set ups. So if I was going to get that set up, the Amsoil EA xxx filter would be very high on the list. It is, like almost everything else in the Amsoil line a tad pricey.

    Bypass oil filter sets ups and synthetic oil use might be a tad off topic in the synthetic thread, but in my op/ed, if you have nothing either mechanically or operationally wrong with your oil or coolant circulation systems; the system is off the hook as far as mileage you can run on the oil goes.

    30,000 miles would be an ARCH conservative figure with such a set up.

    In that same 03 Jetta TDI with oil bypass system with Amsoil EA xxx bypass filter, I'd have no qualms running 60,000 mile OCI's ! I would however change the factory recommended cartridge oil filter app 2 x ( 30,000 miles per) during that period. Of course you'd have to back fill with top up oil. In addition most folks do not realize that an Amsoil EA xxx filter with 2 micron filtration actually filters the oil so that it is FAR CLEANER than it is sold in a BRAND NEW BOTTLE !!!??

    One real advantage here, that most folks do not take under advisement or as part of the equation, that added sump capacity by itself adds proportionate capacity and as a consequence utility. So for example on a 4.5 qt specification, if the bypass system adds a qt, that is 22% more capacity.

    So in proportion if you run say 25,000 miles, you can easily run 5,500 miles more, or to 30,500 miles, and that is before the effects of the bypass oil filter. So because the oil runs FAR cleaner, the wear slows down (the KEY: easily by x half so you can extend the oil change interval 2 x miles or 60,000 miles) , (i.e., less wear metals in solution) and the TBN is not as challenged. So for example, if you set the goal of 5-7 ppm total wear metals (per 1,000 miles) AND you still have TBN left, a UOA will be a useful check to establish a base line. Then, motor ON !!

    Just another tool in the tool box, so to speak.
  • jeffyscottjeffyscott Member Posts: 3,855
    I don't think you should put synthetic in your 200K mi truck. An engine with that may miles on it could go at any time and if this were to, coincidentally, happen shortly after putting synthetic in, the oil may be blamed even though it had nothing to do with the demise of that old worn out engine. ;)
  • ruking1ruking1 Member Posts: 19,826
    That would actually be a good (academic) teaching scenario. However, we were shooting for a 2/3 hour turn around, when the job normally calls for 6 hours. There is a short list of folks, I would trust doing my TB/WP changes and other serious maintenance work. On a practical basis, mechanic disassembly is done on a symptom or break down basis. Neither is/was true in my case.
  • wtd44wtd44 Member Posts: 1,208
    Has any data been generated that would make it possible to compare Quaker "Q" to Mobil 1? Can it be assumed at this point that both are fully qualified members of group IV synthetic lubricants? I am currently using both the Mobil and the Quaker products. I am a little edgy concerning the Q product, only because it is probably a recent entry in the competition while M1 is the old champ. I was drawn into this dichotomy by wanting to use the Q coupon for rebate I found on the Internet.
  • ecotrklvrecotrklvr Member Posts: 519
    Probably. I don't, and guess you don't either. So why do people follow instructions that call for them to use twice or three times as much oil as they need?

    The point is that those are the Manufacturer's "instructions". Like changing oil at 3500 miles.
  • ruking1ruking1 Member Posts: 19,826
    ..."Like changing oil at 3500 miles."...

    In some ways I have a mixed collection of owners manuals.

    The 04 Honda Civic's puts a HUGE emphasis on not classifying ones' self as severe service when "NORMAL" will do. Normal is a 10,000 mile OCI interval (CONVENTIONAL oil). While the oil filter is a tad smaller than a major leaque baseball, they recommend every other oil change or 20,000 miles filter change intervals.

    The 01 Corvette Z06 recommends up to 15,000 miles OCI. The oil filter is slightly larger than a major leaque baseball.

    VW TDI I think really got schooled as it goes from a 30,000 miles OCI in Europe to a 10,000 miles interval, they do not call it SEVERE but as you can see coming down from 30,000 miles is pretty....defacto: in the US. (same VW 507.00 specification oil)
  • wtd44wtd44 Member Posts: 1,208
    Failing to change used up oil can be a very expensive happening. For several decades I have chosen to change oil and filter well before risk of lubricity depletion. I can't say that I regret it, when I consider the outrageous variance with which we are presented for acceptable OCIs. If in fact fresh motor oil is more abrasive than the same oil will be at some x miles of use later, then I can also state that I am convinced that that loss of surface metals (or other loss) is inconsequential to me, given that I rarely run a vehicle beyond 90K miles. And I would venture to say the next owner will never suffer meaningful loss, either. And beyond that, ruking1, I recognize that you never suggested that anything else was bound to be the case, so do not think this is an attack on your Matter-of-fact statement. I suspect you are absolutely right! :shades:
  • ralph1970ralph1970 Member Posts: 28
    It is an accepted fact that synthetic oil is better than petroleum oil. I don't think that oil can can cause the demise of an engine, it is the lack of good oil. That is why I pull a sample of the oil if I have a potential problem, to show that the oil still meets the specifications of the manufacture.
  • ralph1970ralph1970 Member Posts: 28
    I agree!

    I think that the best way to check if the oil is "used up" is an oil analysis. Some say that this cost more than the oil, but I have found that it shows me that I did not go too long for an oil change and other problem that I might have, like a coolant leaks or an air filter problem. An oil analysis has paid off for me.

    I have found that all my cars have been different. My Infiniti could go 25,000 miles, but my Santa Fe may not go 15,000. It all depends on the oil, the car, the oil filter, and how you drive.
  • ruking1ruking1 Member Posts: 19,826
    It is apparent that due to the heaviliy marketed doubts and fears, most folks keep @ the 3,000 to 5,000 miles OCI's, EVEN when the applicable owners manuals say the mileage in plain black and white with the examples I gave in an above post (10,000, 15,000, 10,000 miles dumbed down from 30,000 miles!!!

    Well there is the open but hidden in plain sight secret that some folks might know instinctively, but can't quite put their finger on it.

    The secret is statistically clean oil will not wear significantly enough to cause engine failure. In fact it is VERY VERY REMOTE. (within the normal parameters of driving 12,000 to 15,000 miles per year average age 9.3 years or between 112,000 miles and 140,000 miles ! And the truth is after the meager warranty mileages, they'd be happy to fix for a fee whatever ailments you care to complain about !!??

    They actually use non compliance with the low OCI's to deny warranty service due usually to manufacturers faults or defects; which of course saves a lot of money!

    The other secret is a good grade oil between 3,000 and 15,000 miles will ALSO not wear signifcantly enough to cause engine failure !!!!! Keep in mind that is especially true when oil between 3k to 15k is 10-15% less aggressive !!! . AKA LESS WEAR !!!

    So the third secret is how do the marketers want to play the numbers.!? Do they want to do it for THEIR benefit or... yours... and to be fair a combination. As you can see, MOST err on the side of THEIRS. It still is amazing to me that people pay good money for Honda's (for a lot of reasons) and they think the oem is lying to them when they tell them to run 10,000 OCI's on conventional oil !!!!??? So natually owners think it is good business to run 3,000 to 5,000 mile OCI's.

    So for example, why on earth would you want to change oil on much shorter intervals, when you yourself say you only will keep a car for 90,000 miles????

    So as Ralph and I have said the UOA and especially the total wear metals per 1000 miles are the key measures. When your total wear metals are between 5-8 ppm/1,000 miles, it might be time for a change. But to most folks this is like speaking a language nobody understands let alone trusts.

    Even folks (an even SMALLER population) who take the plunge and actually do UOA's, get caught up in reading a UOA like chinese fortune cookies.
  • ralph1970ralph1970 Member Posts: 28
    A few years ago the president of PQS was quoted as saying that "if we shortened the drain interval by 100 miles for each car serviced, it would mean an additional $20 million in revenue for the company." That was in a Lubricants World interview. Maybe that's why Jiffy Lube and others promote the 3,000 mile change.

    I just wonder how much in the price of a quart of oil are we paying for advertising?? :confuse: The cost of the oil could be only be about 15 cents.
  • jeffyscottjeffyscott Member Posts: 3,855
    I think that the best way to check if the oil is "used up" is an oil analysis. Some say that this cost more than the oil...

    There is that plus a lot of other questions:
    Does a prior analysis showing that the oil was okay after X miles necessarily mean that it will be okay after X miles the next time?
    How many analyses per oil change would you really need to do to be always certain that you are okay?
    If I do it in summer does that mean the results will reflect what will happen in winter?
    What if I drive differently at one time vs. another...eg. going on a long trip on time but not the other?
    Do I trust the guy doing the oil change to get a good, representative sample?
    What is the potential for erroneous results being reported?

    It just seems easier to me to go with the manufacturer's schedule during the warranty. Even if I paid for oil analysis, I'd still do that anyway to avoid potential hassles over any warrranty claim. Both our cars have 5 year power train warranties.

    After all warranties end, I'll still not bother with oil analysis. I'll just go with something like 6 mo./5000 miles for conventional or 12 mo./10,000 for synthetic.

    Since we drive relatively few miles, the time limits will typically actually mean about 4000 mi or 8,000 mi. That part I do wonder about...should I ignore the time based criteria? But I won't do an analysis to attempt to find out the answer, becasue the difference would only be 20% fewer oil changes, which amounts to a savings of maybe $100 per car over a 10 year period, less the cost of the analyses.
  • jeffyscottjeffyscott Member Posts: 3,855
    The cost of the oil could be only be about 15 cents.

    With crude oil at about $70 per (42 gal) barrel, no it could not be, since the crude alone would cost 42 cents per quart. The cost of additives, refining, transportation, and packaging would need to be added to that.

    It's probably far more likely that it is the advertising that might cost 15 cents per quart.
  • ruking1ruking1 Member Posts: 19,826
    Your questions indicate a back ground reading might be more helpful than direct answers to your questions. I think that direct answers to your questions might bring up more questions that will be apparent with a ... back ground reading.

    However, here are some answers to your questions.

    YOU: Does a prior analysis showing that the oil was okay after X miles necessarily mean that it will be okay after X miles the next time?

    ANS: Not necessarily. The real purpose of an analysis (UOA) is to indicate a TREND LINE, once a base line is established. The "UOA's" started in the military years ago for high value and dollar and mission critical equipment, i.e., fighter aircraft jet engines. They were used to confirm or deny maintenance practices. Trendlines would hopefully predict when certain parts might fail to establish MTBF's (mean time between failures). Spot UOA's can also confirm or deny catastrophic failure. You really need to see the numbers presented in context and relationship to the other numbers.

    YOU: How many analyses per oil change would you really need to do to be always certain that you are okay?

    ANS:That can literally vary from one per oil change or so there is repeatability every 1,000 mile increments. So for example, one per 25,000 mile OCI's or 25 each per 1k increments. Again here you are trying to understand the trend line.

    YOU: If I do it in summer does that mean the results will reflect what will happen in winter?

    ANS: No, for the obvious reasons You can of course do 4 per year: winter spring summer, fall UOA's. Yes if you let a winter spring summer pass and then take a UOA. The readings would present an "average" for those three seasons for example.

    YOU: What if I drive differently at one time vs. another...eg. going on a long trip on time but not the other?

    ANS: While you can take a SPOT UOA anytime you wish as per your example, why would you in light of base line, trend line?

    YOU: Do I trust the guy doing the oil change to get a good, representative sample?
    ANS: I would try to get a guy who is used to doing this a lot rather than gee I am just here for the day since I stayed at a Holiday Inn last night.

    YOU:What is the potential for erroneous results being reported?

    ANS: Consistency can be very important. So a reliable lab and repeatable procedures can be important.
  • shiposhipo Member Posts: 9,148
    One of my previous cars derived a benefit from a UOA that had nothing to do with how long any given type of oil would last in my engine given my driving dynamics. That particular UOA found coolant in my oil, coolant that turned out to be leaking past a ten cent "O" ring and finding its way down into the oil pan. Given that coolant is very aggressive at eating away bearing material (such as but not limited to main, rod and cam bearings), had I not performed remedial action, even the factory OCI would have been far too long and it is an almost slam dunk certainty that my engine wouldn't have seen even the 100,000 mile mark much less the 170,000 mark (where I traded it in).

    Long story short, having an occasional UOA performed may well identify a problem that is far more significant than exhausted oil.

    Best regards,
    Shipo
  • wtd44wtd44 Member Posts: 1,208
    We need a well done chart to show the median and average acceptable OCIs for all our common motor vehicles. It should cross reference brands and models of vehicles to brands and sub brands of lubricants. That is, you input the vehicle and your choice of lubricant, the chart/equation spews out the miles you can pretty much count on going for your OCI. :shades:
  • jeffyscottjeffyscott Member Posts: 3,855
    Thanks, I didn't really expect any answers, but yours certainly serve to confirm that for me (a very lazy person) this oil analysis stuff is far too much trouble.

    An unexplained loss of coolant, might be a reason to do it, but then again, finding coolant in the oil via an analysis, would still require searching for the cause...which would be the same thing you would do if you just noticed that you were losing coolant.
  • jeffyscottjeffyscott Member Posts: 3,855
    ...the chart/equation spews out the miles you can pretty much count on going for your OCI.

    It's already in your owner's manual. If the manual is based on conventional, just multiply by 2.
  • ruking1ruking1 Member Posts: 19,826
    Indeed. That is why Kwiky Lubes recommend 3,000 miles OCI. They are playing the more profitable side of the statistics. It is probably easy to see that if they are doing 25,000 mile OCI's, that is a SERIOUS lack of revenue. So for example if oil change shop dollars are @18. (last time I checked the dealers) per oil change, there is/are SERIOUS ( app 8 to 9 (*18)=144 to 162 dollar) revenue loss/es for my 25,000 miles OCI vs 8-9 3,000 miles OCI's.

    But then, the counter point would be what would the average s look like on a sampling of what UOA's looked like from the average Kwiky Lube.
  • shiposhipo Member Posts: 9,148
    The thing was, the UOA pointed out the coolant loss before I had identified that I had a coolant consumption issue. Once the UOA came back I started looking, and between the percentages in the UOA and the relative change in the level of the reservior, I calculated that I was only losing about one ounce per seventeen hours of operation. Said another way, I was losing coolant so slowly that it would have taken something like a year to drain what was in the reservior, however, that was still way too much coolant in the oil to be healthy for the engine bearings.

    Best regards,
    Shipo
  • xwesxxwesx Member Posts: 17,685
    I changed my Caravan (3.8L Chrysler V6) over to synthetic at 173,000 miles. It did not leak or burn oil before hand, and it still does not (215,000 miles now). Last year, I put nearly 23,000 miles on it between oil changes using Amsoil Signatures Series 0w-30 oil and an EaO oil filter. Of course, that engine is not anywhere near "worn out." It still purrs like it was new. So, i think whether or not to switch to synthetic in a high-mileage engine is a matter specific to the situation at hand.

    The electrical system on that van, however, is a whole different story....
    2018 Subaru Crosstrek, 2014 Audi Q7 TDI, 2013 Subaru Forester, 2013 Ford F250 Lariat D, 1976 Ford F250, 1969 Chevrolet C20, 1969 Ford Econoline 100
  • ruking1ruking1 Member Posts: 19,826
    Well the back ground information really doesn't alter the fact that this stuff happens whether you chose to know it or not. Another is the simple yardsticks of a UOA, the oil might need changing between 5-8 ppm total wear metals/1000 miles.

    All the other stuff is a tad like asking for the time and getting detailed classes on how to make and service mechanical watches.
  • jeffyscottjeffyscott Member Posts: 3,855
    I would think you would have noticed prior to draining the entire reservoir. But I don't have any idea how much coolant it would take to be a problem.

    Any chance you'd have avoided the possibility of ending up with too much coolant in the oil with more frequent oil changes? ;)
  • shiposhipo Member Posts: 9,148
    Hard to tell as the coolant loss was so slight that the change in levels could easily be chalked up to just the normal fluctuation due to the engine being at different temperatures when I happened to have the hood open.

    True, more frequent oil changes would have kept the overall percentage of coolant lower, but that isn't really an answer, more a band-aid, and had I not done the UOA, I probably would never have known that I had coolant loss. Even if I did identify said loss, I had no way of knowing if it was loss due to evaporation, a radiator leak, a hose leak, a pump leak, and external head-gasket leak, or the "O" ring leak that was allowing a small amount of coolant to escape into the oil. Long story short, it was the UOA that helped me isolate the location of the leak. ;)

    Best regards,
    Shipo
  • ralph1970ralph1970 Member Posts: 28
    I wasn't serious about the 15 cent cost of a quart of oil. ;)

    It would just be interesting to know how much they spend for advertising to get the public to use more oil changing it every 3,000 miles.

    Motor oil is just one of the many derivatives after the fuel is taken out of the crude oil and It would be hard to figure the cost of any one item.
  • ralph1970ralph1970 Member Posts: 28
    This video shows the 10 or more things that are considered to meet the manufacture needs for new engines to comply with government regulations.

    I wonder how many GF-4 oils now already will meet the GF-5 minimums?

    link title
  • ruking1ruking1 Member Posts: 19,826
    It would seem that the ever changing march of new oil standards has hardly been geared to increased durability and benefit for the consumer. Despite the almost massive chemistry advancements, we still have recommendations of 3,000 to 5,000 miles OCI's. One of the most surprising of these is the Toyota Prius. Almost no Prius owners make an issue of its short OCI. You would think that for as "clean as they run" a 30,000 miles OCI (just like a VW TDI) would be a can do easy.
  • ralph1970ralph1970 Member Posts: 28
    Amsoil has a chart like you suggest for their oils. Go to the below Url, build a list for a car or truck, on the right scroll down to Service Interval, and there you will find a PDF, maybe like what you are looking for.

    link title
  • ralph1970ralph1970 Member Posts: 28
    ---It would seem that the ever changing march of new oil standards has hardly been geared to increased durability and benefit for the consumer.

    ILSAC GF-5 approved oil will need to balance, fuel economy and fuel economy retention throughout the OCI, enhanced robustness, and emission control system protection with phosphorous and sulfer retention.

    Some oils will exceed the minimum standards, but the manufactures will still require OCI for the petrolium oils that just meet the minumins. Those minimums should be high enough to increase the OCI recommendations.
  • ruking1ruking1 Member Posts: 19,826
    Since the community is smaller and the results more know able and focused, there is an interesting debate going on (@www.TDICLUB.com) about the new (5w30) VW 507.00 and the (5w40) MB 229.51 specifications. (DIESEL) as opposed to the gas that you quote.

    While you would never get this is passing conversation, 3 common threads are:

    1. low saps
    2. 5w30 vs 5w40
    2.b. slightly better mpg with app 5.5% lower viscosity (1 to 2 mpg max, but 1% advertised better)
    3. much less aggressive wear metals UOA results (40-70% less with 5w40)
  • ralph1970ralph1970 Member Posts: 28
    there is an interesting debate going on (www.TDICLUB.com) about the new (5w30) VW 507.00 and the (5w40) MB 229.51 specifications. (DIESEL) as opposed to the gas that you quote.


    I would like to read this, but I haven't been able to find the thread.
  • ruking1ruking1 Member Posts: 19,826
    You might try this on www.TDICLUB.com / TDICLUB Forums >VW Discussion Areas > Fuels & Lubricants > TDI UOA Database.
  • beancountantbeancountant Member Posts: 34
    Sir, To go to another topic. A fiend of mine has a Rav 4 with 170k miles. I noticed the coolant was black, like the motor oil mixed with it. Then when I checked the engine oil, it was way low, like it needed almost 2 quarts. Could this be a Head Gasket problem? I know if the coolant goes into the engine and mixes with the engine oil, it's probably a head gasket, but this is the reverse. The engine oil mixes with the coolant.
    Any Suggestions what her problem is??
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Does this vehicle have automatic transmission? If so, it could be a defective radiator, which has two tanks built into one---one for coolant, and the lower tank to cool the transmission fluid. So if the two tanks mingle fluids, there you go. I'd check the transmission for coolant as well. (not good).
  • ralph1970ralph1970 Member Posts: 28
    A UOA might be usefull here for both the engine and transmission.
  • ruking1ruking1 Member Posts: 19,826
    It certainly sounds as if it might be.
  • wtd44wtd44 Member Posts: 1,208
    What awful prospects! None are good.
  • jeffyscottjeffyscott Member Posts: 3,855
    I had oil in coolant due to head and other gasket failures in a Ford Windstar, so yes it can go that way.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    A cracked cylinder head can sometimes do that----oil in the coolant. I'll bet you'll find coolant in the very bottom of the oil pan, too, should the radiator/transmission cooler tank theory prove not to be correct. You should also check for low level in the transmision fluid. If it's low, that's a good indicator that the "oil" in the coolant is transmission fluid.
  • ruking1ruking1 Member Posts: 19,826
    I read in passing that Toyota starting with2007 MY, began going to the 5w20 with 0w20 optional/preferred.

    Current models, I have also read have gone to the 0w20. They have also gone to the 10,000 miles OCI. There was no word what has caused the switch. It could have been the switch to GF-5/ ILSAC, or perhaps Toyota had decided it was about time to "get with it. "
  • ruking1ruking1 Member Posts: 19,826
    I forgot to add that this is a good signal from an engineering point of view. This increases the probablility Toyota has tested or at least re engineered their old "oil cooking"(aka sludge monster) engines with the new standards (GF-5/ILSAC) on the front burner.

    I have been running 0w20 (and if on sale 5w20) Mobil One in a 04 Honda Civic @ 20,000 miles intervals since the first 10,000 mile (CONVENTIONALoil ) factory fill. Even at that I sometimes feel like a belt and suspenders fuddy duddy.

    I would have been more than skeptical if I had gotten a 04 Toyota Corolla instead.
  • ralph1970ralph1970 Member Posts: 28
    The ILSAC GF-5 oils will not be ready until the last quarter of 2010.

    I read some place that only about 10% of owners are using synthetic oil.

    I think that OEM's base the OCI on petrolium oil meeting the minimum standards and their warranties writen by lawyers.

    Thirty year ago, when I started using synthetic oil, synthetic oil was group IV or Group V base stock only. About ten years ago it was ruled that Group III petrolium oils could be marketed as synthetic. Now there's no definition of synthetic oil.

    Both the OEM's and oil manufactures set OCI's recommendations not only on miles, but also on how we drive, normal or severe, and a time period, like every six months or once a year.

    Then there are some vehicles that have been reported prone to sludge problems, like Audi/VW, Lexus/Toyota, Chrysler/Dodge/Jeep, Saab and Subaru.

    The question that I see most is, how much can we increase the OCI without damage to the engine with the use of synthetic oil?

    There is no one lubricant or OCI that fits all of our needs. The best lubricant is the one that achieves its purpose in a specific application for a specific desired service life at a minimal cost, both financial and environmental.

    Man-made products are better because the performance and composition is more predictable and more consistent, than composition of products from natural sources. Base oil produced from crude oil can vary in specifications and performance, and can not be totally predictable.

    For me the way that I confirm the OCI is with a used oil analysis (UOA). The UOA does not predict the future of the oil, like a fortune cookie, It just tells me the condition of the oil at the time I took the sample. What has worked for me has been once a year when I change the oil, 13K to 20K.

    For others it might be every six months. That might be a good place to start to see if you could go longer. You do not have to drain the oil to get a sample. You can pump it out through the dip stick tube.

    There are several things I look for in the physical properties and degradation of the oil in the UOA report, that I feel are important.

    The TBN tells how much life is left in the oil to take care of any acid. TBN depletes with use.

    The viscosity of the oil. The OEM tells us what viscosity we should use and I want to keep it in that range for proper lubrication.

    The oxidation and nitration levels because these increase viscosity, acid, sludge and varnish formation.

    The presents of glycol, water or fuel. These would indicate engine problems that could be detrimental.

    UOA takes the guess work out of when to change the oil and gives me piece of mind for a very low cost. The low amount of wear metals confirms that the oil has done what is was supposed to do, lubricate.
  • shiposhipo Member Posts: 9,148
    A couple of comments:

    - About ten years ago it was ruled that Group III petrolium oils could be marketed as synthetic. Now there's no definition of synthetic oil.

    - - The above statement is basically true in North America; not so in Europe.

    - Then there are some vehicles that have been reported prone to sludge problems, like Audi/VW, Lexus/Toyota, Chrysler/Dodge/Jeep, Saab and Subaru.

    - - To narrow your brush stroke a bit for the VW/Audi world, only the 1.8T motor is known to make sludge (and only when non-502.00 certified oils are used). As for the Chrysler/Dodge/Jeep world, the only one of their engines that is a known sludger is the 2.7 liter V6.

    Best regards,
    Shipo
  • xwesxxwesx Member Posts: 17,685
    And I am very curious how Subaru founds its way in there; that's the first I've heard of it! Subaru engines have had prone failures in the past, but not for sludge issues!
    2018 Subaru Crosstrek, 2014 Audi Q7 TDI, 2013 Subaru Forester, 2013 Ford F250 Lariat D, 1976 Ford F250, 1969 Chevrolet C20, 1969 Ford Econoline 100
  • ralph1970ralph1970 Member Posts: 28
    And I am very curious how Subaru founds its way in there; that's the first I've heard of it! Subaru engines have had prone failures in the past, but not for sludge issues!

    My son has a Subaru and I found this out when I ordered oil for his car. It is a problem with all turbo equipped cars. The turbo charger oil mesh screen gets clogged or restricted reducing or cutting off oil supply to the turbo resulting in failure. See their service bulletin 02-103-07 dated 10/19/07.

    Subaru recommends that the engine oil and filter be changed every 3,750 miles or 3-3/4 months. In addition the mesh screen should be checked to be sure it is not clogged or restricted.

    My son is using synthetic oil and and a good oil filter, and has not had a problem.
  • xwesxxwesx Member Posts: 17,685
    Oh, yes, yes. I was thinking you were referring to the engines; I was not thinking about the turbo units at all.
    2018 Subaru Crosstrek, 2014 Audi Q7 TDI, 2013 Subaru Forester, 2013 Ford F250 Lariat D, 1976 Ford F250, 1969 Chevrolet C20, 1969 Ford Econoline 100
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