Ford's new 5-20 oil

fagodfagod Member Posts: 1
edited March 2014 in Mercury
I would like to know more about Ford's new 5-20 motor oil. What is the difference between this and a 5-30 that you can buy at your local auto store. Would there be any bad consequences in using a commercially available 5-30 instead of Ford's 5-20 on a new 2002 Mercury?


  • brucer2brucer2 Member Posts: 157
    From what I've read on the CEG (Ford Contour Group) from a knowledgeable Ford tech, the new Ford 5W-20 is a Group III base stock, SL grade oil. Ford is not only recommending it for all new cars, but also issued Tech. Bulletins stating that it is now the perfered oil for most engines that originally called for 5W-30. Aside from being a high quality oil (close to synthetic), AutoZone sells it $1.49 a qt.
    I won't address the issue of whether, or not, it's adviseable to switch to 5W-20 from 5W-30, or long term relability of engines using the lighter weight oil.
  • 8u6hfd8u6hfd Member Posts: 1,391
    Ford & Honda spend considerable time doing durability testing and accelerated life testing to see if 5w20 will affect reliability. The 5w20 oil is to increase the fuel economy a bit. I defintely know Honda puts 5w20 in the Insight & Accords (after MY2000).

    Switching from 5w30 to 5w20, I wouldn't recommend doing.
  • stealth1969stealth1969 Member Posts: 162
    has it for $1.33, at least at my local store. On the bottle it says it is a synthetic/hydrocracked base oil. The same base as Syntech but for $3 less.
  • wtd44wtd44 Member Posts: 1,211
    Perhaps the larger issue is if any manufacturer (Honda, Ford?) DEMANDS that 5-W20 be used, under threat of warranty loss, or some such. If the goal is mileage, and that alone, I would think they would care less if you used 5W-30 instead, once they have the CAFE certification in hand. A car buyer really needs to know the answer before buying.
  • brorjacebrorjace Member Posts: 588
    Well, I believe the durability studies showed that cars using this stuff COULD make it to the 150,000 mile mark ... but by using this extremely thin oil and going any longer than 3,000 miles between oil and filter you are compromising your vehicles long-term durability.

    Personally, I would only use it during the warranty period and then switch to a synthetic 5W30.

    The dealership changed the oil in my dad's 2000 Mercury Grand Marquis and when warm, 5W20 had the consistency of water.

    All this to get another 1-2% fuel economy? I don't think it's worth it.

    --- Bror Jace
  • gslevegsleve Member Posts: 183
    Thinner motor oils such as 5W-20 or even 0W-20 are becoming more popular these days and are even specified by some OEM's (FORD & HONDA) on new 2001 cars.

    Although these oils are promoted as "energy conserving" they generally trade a gain of less than 0.1 MPG in Corporate Average Fuel Economy (CAFE) for shorter useful engine life.

    FORD which has previously designed cars to have 10 year or 150,000 miles life has reduced the mileage life expectation to "beyond 100,000 miles" on vehicles that are operated on SAE 5W-20 Motor Oil.

    HONDA only claims "useful life" as 7-years or 70,000 miles in EPA certifications for their CIVIC which uses SAE 5W-20 Motor Oil, while the previous model that utilized SAE 5W-30 Motor Oil was certified for 10 year or 100,000 mile durability.

    Since both HONDA and FORD Warranty their NEW cars for ONLY 3-years or 36,000-miles the reduction in engine life expectancy is not a factor.

    By contrast Mercedes-Benz recommends use of ONLY Synthetic Motor Oil that is at least SAE 5W-40! This is a recent increase in recommended viscosity from SAE 5W-30. Apparently customer research indicated that engine longevity is more important to typical MB customer than fuel economy.

    Even more important is the High-Shear High-Temperature MINIMUM specification in SAE J300. In tables below you will notice that there are "two" SAE 40 specifications, one with minimum HSHT value of 2.9 cP for Automotive Oils (SAE 0W-40; 5W-40; 10W-40) and the other for Heavy Duty Oils (HDO) (SAE 15W-40; 20W-40; 25W-40; 40).

    This double specification is at insistence of heavy duty engine manufacturers who have required HSHT viscosity limits consistent with good engine durability in high-load, severe service operation. HSHT value of 3.7 cP or 27% more viscous oil at 150ºC (300ºF).

    Yes, a 27% increase in viscosity makes a difference between Automotive engine that lasts 100,000 miles and Truck engine that lasts 1,000,000 miles!

    When you consider that most Automotive Motor Oils are ONLY 3 cP
  • mbbenzmbbenz Member Posts: 47
    Mercedes does recommending Synthetic on all their MY98 and newer vehicles where they have the integrated FSS (Flexible Schedule Service) computer. They will pay for the Synthetic as part of schedule maintanance. Also just so you know Mercedes does not say that the oil has to be 40 grade or thicker. In fact the list of MB approved motor oil that MB sent me includes various brand and viscocity for the Synthetics they recommend. It has Syntec 5w-50, Mobil1 0w-40 and 15w-50, Shell helix Ultra 5w-30 just to name a few. My local dealers use Mobil1 0w-40.
  • mrdetailermrdetailer Member Posts: 1,118
    Check the Engine Oil, a slippery subject for more discussion on this issue. Castrol indicates that there is conventional oil, lowest on the scale for duability, synthetic, highest in durability, and hydrocracked is listed as being between.

    I have received the spec sheets for both conventional, synthetic and hydrocracked from both Valvoline and Quaker State.

    Valvoine conventional, Duralube Synthetic Blend, Maxlife, and Syntech were the ones I compared on the Valvoline side.

    Quaker state was Conventional, 4 X 4 Synthetic Blend, High Mileage for Older Engines and Ultra Premium Full Synthetic

    Synthetic blends were a little bit better on flashpoint, but generally were close to conventional oil. None of these specs listed anti-wear abilities.

    Hydrocracked were much closer to synthetic oil on the sludge test, and flashpoint, but were only a little better on cold starting. They were about 5 degrees colder than conventional.

    In Synthetic flash point was the highest. Cold weather starting was truly superior, and the additive package was amazing. This is the one that really should be used for extended oil drains. On most Sludge tests quite frankly, it is inadequate. Most can do double the time of conventional oil tests without any problems.

    TBN for a conventional oil is 4. TBN for Synthetics is generally 10. Generally the higher the TBN the better the additives and durability.
  • mrdetailermrdetailer Member Posts: 1,118
    Here is some information I found on Valvoline

    All Climate 5W-20 is formulated with advanced additive technology and highly refined, premium quality basestocks to protect todays most sophisticated engines against wear, undesirable deposits, contamination, nad viscosity and thermal breakdown under service conditions. It is specifically designed to meed the demanding requriements for 2001 model year Ford, Mazda and Honda engines where a 5W-20 is recommended.

    Valvoline 5W-20 Motor Oil advantages.

    High Temperature Protection: -- resists breakdown in the most severe engine environments.

    Low Temperature Protection: Flows easily at low temperature startups.

    High Detergency: fights formation of sludge and varnish.

    Wear Protection: contains anti-wear additives that dramatically reduce engine wear

    Reduced Burnoff: formulated with advance base oils that resist vaporization, thus helping to reduce emissions.

    Fuel Economy:Improves fuel economy throughout the life of the oil.

    Meets API SL, ILSAC GF-3, Energy Conserving, and specific Ford Recommendations.


    I compared the specs and based on that information, and the constand referral to highly refined basestocks, it is pretty clear to me that this is a hydrocracked oil. Can't be sure because Valvoline considers much of this to be proprietary information.

    While not as good as synthetics, hydrocracked oils are a very good quality.
  • inkieinkie Member Posts: 281
    I was reading the precedeing messages and notice your interest in "hydrocracking" This process is used on petroleum or its products in the presence of hydrogen and catalysts. So 5W20 is definitely derived from petroleum products. I just bought a Honda CRV and they specify 5W20 and recommend oil changes at 10,000 miles on normal conditions. I usually never go beyond 3,000 miles so this is amazing if its true. I will probably use 5W20 and change my oil every 5,000 or 3or 4 months.
  • adc100adc100 Member Posts: 1,521
    I believe you are right on the money. I had also heard that Ford had backed off of the durability issue. Or more properly I asssume the EPA backed off of the requirement. Hmmmm.... can you say Political Contributions??? Anyway-yes, durability has been sacrificed in the name of CAFE. There is no way I would e-v-e-r consider the use of this viscosity oil.
    Where did you get the info on the HSHT??
  • zfrankzfrank Member Posts: 6
    Have a 2001 Ford Ranger . Book calls for 5W-20. Son gave me a case of Havoline 10W30 for Christmas. Called two local Ford dealers, one said "no problem,use the 10W30", other said, "only use the 5W-20".So I sent Ford Customer Relations e-mail reiterating foregoing. They quote manual along with alot of corporate BSBSand won't answer yea or nenea.So can I use the 10W30 , or must I use 5W-20, or should I go to a complete synthetic, and if so what weight? Please relieve my frustration. I live on the coast in Virginia and drive a mamaxf 5k a year. I'm just an old F---.
  • adc100adc100 Member Posts: 1,521
    Living in your area I would go with the 10W-30 Synthetic. Preferably either Mobil 1, Quaker State, Valvoline, or Amsoil. The reason for syn is a hedge against the unknown issue of a real requirement for the 20 weight. Syn just gives an extra measure of overkill. I would be a little afraid of the 10W-30 conventional oil. But then again I'm somewhat paranoid.
  • carnivaljcarnivalj Member Posts: 12
    I guess I'm being dumb but I'm not really understanding what is supposed to be wrong with the 5W20 oil that my new Honda CR-V maual says to use? Please explain. Maybe I'm just misunderstanding. Does thinner mean that it won't protect as well as the 5W30 my Civic and Accord used?
  • brucer2brucer2 Member Posts: 157
    If you drive 5,000 miles a year, and plan on keeping the Ranger 10 years, changing the oil twice a year seems reasonable to me. Do spring and fall oil changes with the 10w-30 in the spring and 5w-20 in the fall.
  • adc100adc100 Member Posts: 1,521
    The problem with 5W-20 is that you have the 20 weight at operating temperature as opposed to 5W-30 where you have the 30 weight. The 30 weight has a higher viscosity and therefore higher liquid film strength wich would normally allow metal parts rubbing against each other to have better protection than the 20 wt. The trade off is that overall the 20 wt has less viscosity and therefore in locations of lower loads would have less fluid friction. Consequently the 20 weight will give a slightly higher milage (at the expense of wear in higher loaded areas) which allows Ford to build more SUV gas guzzlers. Higher CAFE The EPA recognized this probability and required ford to prove that their engines will last 150K (I believe thats the number) Somehow that requirement was modified/changed/deleted-who knows. You figure it out.
  • fivespeedfivespeed Member Posts: 42
    Ask your son to take back the 10w30 and get 10w20. I'm sure that he won't mind since it was his gift to you.

    If the manufacturer recommendation is 10w20, then follow it!
  • mrdetailermrdetailer Member Posts: 1,118
    My Jiffy Lube manager saw a film that showed the damage that 10W-30 could do to the engine valves. He said the heavier oil couldn't get through the clearances. This was conventional. If you are going to break away a 5W-30 syn would probably be a better choice.

    With that weight oil I would never consider 10K intervals. Like the sludge site, compliance with the time and distance on the severe schedule will protect you during the warranty period.
  • dtownfbdtownfb Member Posts: 2,918
    If the owner's manual says use 5W-20. then use it. What's the problem? The manual and maintenance schedule are written by the manufacturer of the vehicles. Their recommendation for maintaining the vehicles that they built is to use 5W-20. Why is everyone trying to justify the use of this oil? Honda and Ford built these vehicles. Shouldn't they know how to maintain them? Plus if you were to use a "thicker" oil and something happened to your engine, do you think either manufacturer will stand behind the vehicle? No!

    If the manual says use 5W-20 and change the oil after 10,000 miles then do it. Less money out of your pocket and less time at the garage. Engines are made much better today then they were just 5 years ago. They burn much cleaner, require less fuel and have tighter construction. It makes sense that a thinner oil is necessary to lubricate the engine.

    It is interesting to hear about all the new oil technology. This should tell you how far oil has come in the past 10 years. Remember the 90's when oil companies had us all brainwashed about changing the oil every 3000 miles. Now the recommentdation is every 5000 miles minimum but mostly 7500 and 10,000 miles. Which is great. it's the first step to the US becoming less dependent on foreign oil.
  • brucer2brucer2 Member Posts: 157
    Manufacturer maintenance schedules are set to get owners through the warranty period without major problems. Since most folks are more than happy not to spend money on preventive manitenance they are happy about this. A more aggressive manit. schedule could extend the life of a car by at least 50%. How much oil do you think that would save.
  • armtdmarmtdm Member Posts: 2,057
    well, since the trend is to place cheaper parts in new cars in general and since there really is no data out there to support the 5W20 I guess most people are very reluctant to trust the auto manufacturers who we know can build more durable cars but who also need to sell more cars and sell service. A real problem

    No doubt this same issue occurred when the switch was from 10W40, the common weight years ago, to 10W30. When the 5W30 weights first came out there were numerous reports of the oil saving gas but not protecting as well, so same scenerio here
  • joe3891joe3891 Member Posts: 759
    The qt of Motorcraft 5W-20 i looked at stated on the container semi-synthetic.
  • brorjacebrorjace Member Posts: 588
    dtownfb, were you being serious or playing "devil's advocate"?

    The auto manufacturers don't want your car to last more than 100,000-150,000 miles. This new, ultra-thin 5W20 oil is designed to allow them to sneak by some EPA CAFE rules ... not designed to protect your car better. The tolerances on every Ford and Honda have NOT changed between 2000 and 2001.

    Tentax, you'd be better off not typing in all-caps.

    joe3891, the word "synthetic" does not necessarily mean what it did a few years ago. The oil producers are diluting their formulas with heavily processed crude oil and calling it "synthetic" even though REAL synthetic is made from ethylene gas (polyalphaolefin) or the combination of certain acids and alcohol (polyol ester).

    --- Bror Jace
  • vwracervwracer Member Posts: 90
    too hard to read......ever see a newspaper or magazine printed in all capital letters?....
  • alcanalcan Member Posts: 2,550
    It's also considered to be the equivalent of SHOUTING.
  • joe3891joe3891 Member Posts: 759
    My point was its not the run of the mill 5W-20 oil.
  • brorjacebrorjace Member Posts: 588
    Since it is a breach of accepted netiquette to intentionally type messages in ALL CAPS on forums such as this, I'm afraid you'll have to get used to your messages being ignored by people who do not like reading them.

    Effective communication requires cooperation between the sender and the receiver but the sender's role is more important and he/she should do everything he can to get his message across clearly and effectively.

    --- Bror Jace
  • mp5freakmp5freak Member Posts: 51
    Yep - I just skip messages in all caps. Ya want it read, learn how to type in lower case and use the shift key for the occasional capital.
  • mrdetailermrdetailer Member Posts: 1,118
    I do now for a fact that the Quaker State 5W-20 is semi-synthetic even though it doesn't say so on the bottle. This is according to the Qstate technical support. It has to be to meet Ford standards for durability.
  • kirbstoykirbstoy Member Posts: 53
    I have been a Mobil-1 fan for many, many years and have never encountered ANY oil-related problem in numerous vehicles. So, when I read that Ford recommended 5W-20 oil for my new Focus ZTS and then determined Mobil-1 doesn't make a 5W-20, I simply used Mobil-1 5W-30. I can't imagine a scenario where Mobil-1 will fail to provide proper lubrication. On numerous occasions last summer, I sat in Sacramento commute traffic for in excess of an hour (With A/C running) in 100* or hotter weather. The temp. gauge never even moved off its regular position. I'll stick with Mobil-1 5W-30!
  • adc100adc100 Member Posts: 1,521
    I wouldn't be afraid of 10W especially in your climate either. I maintain a bunch of cars - not all mine (8) and use the 10W in all- even in Pennsylvania.
  • csandstecsandste Member Posts: 1,866
    E-mail Etiquette (Netiquette)

    By Chris Pirillo

    "This part of the chapter is not just for newbies; even if you've written e-mail for years, review this section carefully. Certain unspoken conventions are very important to keep in mind when you're composing e-mail messages. If you were a novice before, you need to be a professional now.

    ONE OF THE BIGGEST MISTAKES PEOPLE MAKE IS TO TYPE WITH THEIR CAPS LOCK ON. All-caps might look cool to you, but experienced users will write you off as an idiot. It's okay to use all-caps for headings and/or titles in your messages, or even to EMPHASIZE certain words, but anything beyond that is equivalent to screaming at someone. Do you like being yelled at?"

  • mbbenzmbbenz Member Posts: 47
    Thank you. Another word, the guy tentex is an IDIOT !!!!!!!!!!!!!!!!!!
  • dtownfbdtownfb Member Posts: 2,918
    Actually brorjace I was quite serious. My point is we are arguing the validity of a certain engine oil that the manufacture of the vehicles recommends. As if any of us has better knoiwledge then the person who designed and built these vehicles. The 5W-20 could be for better mileage efficiency. Is there something wrong with that? Call me stupid but didn't we just go through $2.00/gallon gas prices across most of the nation less then a year ago? Aren't gas prices starting to inch ther way back up now? And if an engine is running more efficiently, shouldn't the engine last longer?

    If you change your oil yourself, I would use 5W-30 until the 5W-20 becomes more readily available and cheaper. Right now Jiffy Lube, Walmart (in PA) and Lube Express are charging a premium for this oil which isn't fair to the consumer.

    BTW, the 2 vehicles I have seen switch to 5W-20, Ford Focus (new for 2000) and Honda Civic (major re-designed for 2001) including some engine modifications. So yes, the standards for these two vehicles has changed. I'm not aware of any other vehicles in the Ford or Honda line recommending 5W-20. But I'm sure if there are some, you will tell me.
  • mrdetailermrdetailer Member Posts: 1,118
  • armtdmarmtdm Member Posts: 2,057
    Just happened to see it in the showcase today, container says semi-synthetic.

    On another note, in todays world of Firestones, Ford fiascos, Castrol mis-leading advertising, Toyota sludge, constant manipulation of quality for the sake of profit how can one possibly totally believe what a vehicle manufacturer states as the best lubrication for long term durability. They have one goal in life, stockholder value via mazimixing proft. The fine line is to give the customer the perception of quality while building in obselesence. Now if they published reports of their long term mileage tests with the 5W20 etc but to just say use it??? Personally, i will not purchase a car that recommends this weight until long term results are known. There are too many alternatives out their with proven weight recommendations. Do you honestly believe that Honda will replace engines on thousands of units where the recommended oil was 5W20 when they blow at 100,000 miles, NO WAY!!!!!
  • gregb882gregb882 Member Posts: 75
    The 2002 Explorer/Mountaineer with the V-8 engine recommends 5W-20. The V-6 still calls for 5W-30.
  • 8u6hfd8u6hfd Member Posts: 1,391
    Honda won't replace an engine if you misshift in a RSX Type-S or S2000. Honda is very stingy about this stuff.
  • vwracervwracer Member Posts: 90
    Bought a new F250 few days ago with 5.4L V8. Owners manual calls for 5w20. Went to Auto Zone yesterday and they had three national brands of dino 5w20 with no difference in price as compared to other weights of the same brand. Wonder if any synthetic brand will make 5w20.
  • armtdmarmtdm Member Posts: 2,057
  • cpearson1cpearson1 Member Posts: 30
    <<They have one goal in life, stockholder value via mazimixing proft>>
    Enron apparently didn't have the goal of stockholder value or maximizing profit. Should we give them a civic responsibility award?
  • armtdmarmtdm Member Posts: 2,057
    The execs did maximize profit when they sold out when the price was still high before the word got out they were bankrupt!
  • brorjacebrorjace Member Posts: 588
    dtownfb, To keep this short, the car companies treat the average owner like an idiot. They (and their dealer partners) often talk down to owners, condescend and otherwise give them advice that is basically, sorta OK, for the most part. But, it is dumbed down, to be sure.

    Maybe the 'average' owner deserves such treatment as they put little thought into maintaing their car ... but I am certainly not average in this respect.

    And, as others are fond of pointing out, their motives and goals are not necessarily parallel to my own. They want to meet CAFE standards cheaply, stupidly and possibly foolishly.

    I prefer to obtain VASTLY superior fuel mileage through the use of higher tire inflation pressures, superior quality electronic components, synthetic lubricants and a careful driving technique.

    --- Bror Jace
  • pigloverpiglover Member Posts: 25
    I know oils have improved, but high operating temperatures and high speeds have always required a heavier oil. I find it hard to believe that Ford makes no exception; for example, a car driven in a hot climate. The protection against wear offered by 5w-30 in Arizona in July has to be better than 5w-20. I live just north of New York City and I'll let the dealer put 5w-20 in in the cooler months. But from June-Sept its 5w-30 for me. (Remember Castrol's 20w-50 for today's high revving engines?)
  • zr2randozr2rando Member Posts: 391
    I hate to say it but while the vehicle is under warranty we should go by the book, don't want to give the manfg the excuse to not cover anything at that point.
    BUT! (Notice the CAPS), after warranty, I say thicken up folks! I could care less if my vehicle gets .5 mpg better under perfect testing conditions....I don't want to replace the motor!
    I consider the 10w30 about as thin as I can stand (I live in NC so don't have any problem with extreme cold), I prefer 10w40 (I know, a lot of VI but have never had a problem with it,,just change it very regular...) and personally, during the summer.....gasp!!!.....believe that 20w50 is the way to go....After the motor has worn in it has some wear that opens up the clearances anyway.
    The folks that want us to use 5w20 just want the vehicle to rate a little better gas mileage (CAFE)(heavy push by the gov't probably can't blame them) and could care less about us keeping it long term....Personally I am more interested in keeping the vehicle a long time, I get kinda used to'em.
    That's my opinion, I'm sticking to it, y'all with me or am I swinging the bat in all directions???
    see y'all in a bit
  • csandstecsandste Member Posts: 1,866
    Mark Salem does a radio show in Phoenix and St. Louis. To me he seems knowledgable. Although I have some qualms about 5W20, I'd have more problems with 10W40 or 20W50, especially in a new engine. I posted this once before and got cutting remarks about Jif or Skippy, but to quote Mr. Salem:

    "If you drive your car hard and you are in the city 95% of your time, then you can use either a 5-30 or 10-30 SH or SJ oil. We should use an oil that protects us between the temperature range we live in. Using a 5W-30 or 10W-30 oil will generally give you 1-3% better gas mileage than a 30 weight or 20-50 weight oil. Thinner is better, both for your engine and your pocketbook.

    I know that putting a thinner oil in your car goes against everything you have been taught. Most of us cringe at the thought of putting a 5W-30 in our engine. First, you must understand what motor oil is supposed to do.

    1. Oil is used to provide lubrication between two moving parts to reduce wear. Most internal engine tolerances are measured in thousands of an inch and many tolerances are no thicker than a human hair. So, if you wanted to fill an opening with oil that was no thicker than a human hair, which would do a better job, peanut butter or sewing machine oil?

    2. Oil is used to gather or absorb heat from the internal engine parts and carry it away. Let's say two pieces of metal are rubbing against one another at say...50 times a second or 60 MPH. If we want to flush this joint with oil and keep a continuous stream of oil running through and over it to gather the heat generated and carry it away, would you use peanut butter or sewing machine oil?

    3. Oil is also used to flush the metal particles from the bearings of your engine. This one should be easy...peanut butter or sewing machine oil?

    4. 90-95% of all mechanical engine wear occurs in the first 10 seconds of a cold engine start up. That initial cold start wear can equal hundreds of miles of warm engine wear.

    So.... you it's your choice, peanut butter or sewing machine oil?

    There are situations that call for a thicker oil. In the event your car consumes an abnormal amount of oil between oil changes, using a thicker oil would be beneficial to you. A thicker oil would, in this case, help you control the oil consumption. An abnormal amount is generally described as more than 1 quart every 1000 miles or so.

    But keep in mind that every car made in 1993 and newer recommends a 5W-30 or a 10W-30. We must work to overcome the idea that thicker is better unless of course there is a reason.

    I hope by now you are convinced that peanut butter type oils no longer belong inside your engine. We now know thinner is better."

  • zr2randozr2rando Member Posts: 391
    I understand how thinner oil can perform better for several of the requirements that you mentioned above, especially in a new engine (low miles and late model).
    For an engine that has more than 50k on it, even a modern engine, during the heat of summer, I still think some additional viscosity comes in very handy. When it is in the 90's and the engine is trying to handle the heat of the ac running plus normal generated heat...even 20w50 is not all that thick. The comparison of peanut butter and sewing machine oil is a bit extreme, I would probably have used corn oil(10w30) and peanut oil(20w50)...with water being the 5w20...
    I do think that during cold weather thinner oil performs great, helps avoid lack-o-lube for that first minute or two.
    I still believe that the manufactures are under significant pressure to get better gas mileage and thinner oil helps (a couple of percent may help the CAFE but doesn't help me).Any gas mileage gains come at the expense of engine longevity which they are NOT under as much pressure to provide..and is MY main concern.
    It would be nice if there was a 5w50 that REALLY performed like the 5w50 implied without all the VI side effects..I guess I'm still just part of that old F--- club too huh?
  • dudleyrdudleyr Member Posts: 3,469
    I am by no means an oil expert, but I always thought that an oil lost its viscosity during use.
    So that say a 5w-30 oil eventually became something closer to a 5w-20 after so many miles. Also oil drain intervals are getting longer and longer. Some manufacturers reccomend up to 10,000 mile change intervals.

    While, like many others, hesitate on the 5w-30, my thoughts are as follows. If it is OK to run regular 5w-30 oil at 5,000 miles when the viscosity has broken down some, why is it not OK to run synthetic 5w-20 which will not break down nearly as much if at all? I can see resistance to 5w-20 dino oil, but I think synthetic should be alright - don't know about the blends like motorcraft.

    Interestingly it took me a long time to switch from 10w-40 because I thought 5w-30 was way too thin. Part of the reason we used 40 weight back then was to counter the rapid breakdown of the SC rated oil that was used back then - compared to SL (think that is the most recent) that is available today.
  • csandstecsandste Member Posts: 1,866
    Personally I use what the manual says to use. I have an Elantra which recommends 10W30 and use that except during the winter. Have a Cavalier which recommends 5W30 and have stayed with that though I'll probably change to 10W30 as the mileage gets past 80K and the engine wears a bit. I wouldn't put an oil without an API seal in a car calling for it. That excludes all 10W40's and 20W50's.
  • zr2randozr2rando Member Posts: 391
    While under warranty, follow the rules, no question. Thing is all my vehicles don't even remember their warranty days,,,Chev and Nissan couldn't care less what I do with those vehicles now. I'm sure it was just statistics catching up with me but of all the vehicles I've ever owned, I have kept most of them to around 200k, I have had 1 major oil related problem (95 Chev Blazer 4.3 v6 that spun a cam bearing, got metal in the crank bearings ,,or vice versa...), Book said to use 10w30 and that is all I used,(first vehicle I ever used 10w30 in), that engine died at 107k, now I have a GM reman engine in it with a 50k warranty so I am using 10w30,,,,until 50k,,,then I will thicken up a little on that one. If the manufacturer will factory warranty the engine for 100k using lightweight oil then I will believe they are truly looking out for the engine, otherwise I believe they are just trying to improve the CAFE ratings.
    Just a personal thing with me I guess, but the only vehicle I ever used 10w30 on , engine died an early death. I sincerely hope everyone else has better luck than me on that issue.
    All the arguments for using the thinner oils make sense, just my experience says it does not work for me.
    That one engine caused me more $$$ and headache than all the repairs and $$$$ on all my other vehicles so far put together, like I said though, probably just statistics catching up with me...
    I don't particularly care for black cats either, and I don't walk under ladders.
    see y'all
This discussion has been closed.