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Synthetic Engine Oil

Synthetic Engine Oil

Synthetic Engine Oil

(OP)
I did a search for this one also with no luck.  Sorry if this has been asked before.  I put this in another thread rather than combine it with my question on High Mileage Oils.

So, I have a car with 120k miles on it and have always run the standard 10W-30 from one of the local quick change marts: non synthetic I assume.

I've heard stories of going to synthetic after so long on the natural stuff and have heard of gumming and leaks.

Any one out there with the real story?

Plus, my wife will be getting a new car soon.  The dealer is giving 3 free oil changes.  Is it worth starting from the beginning with synthetic and lengthening the time between oil changes?

Oh.  I'm looking for a layman's answer.  I have no idea what you guys are talking about when you get into acids and the better weights.

This is normally the space where people post something insightful.

RE: Synthetic Engine Oil

Laymans answer? Hmmmmm!
Well, synthetic lubricants are pretty much the IN thing right now...note I did not say the BEST thing.  In your case, you have already 120k with now problems (I have gone over 380k on std lubricants with a 77 360 Dodge and I drive a 75 year old car that, while it is on Mobil 1 now, spent most of it's life on regular 'rot gut' oil of indeterminate quality.  The change to syn was uneventful about five years ago...just drained out the old and added the Mobil 1 15W-50 and drove away...no problems yet.

I use synthetic in my race engines because I perceive it to be superior...however, I never lost an engine to lubrication failure using Castrol 30R/40R and later 20W-50 in some 40 plus years of racing prior to changing to synthetic.

Oil change intervals?  I use 3000 on my wife's Lincoln and 6000 on my Dodge diesel(13 qts).  The current recommendations vary from 3000 to 15000 depending on the OEM.  Mobil 1 will now warrent their product for extended, up to 15,000 miles, change intervals.  I see no problem with this in MY case and that is not to say EVERY case (I will continue to change at 6000).  I spent most of my career changing oil and filter at 3000 mile intervals so this switch to 6000 miles is a milestone for me.  The '01 Lincoln has 130k and the'91 Dodge has 200k---all with zero problems.

Bottom line:  If you live in the desert southwest and tend to drive at 90 to 100 mph as every one else, change more frequently and use a synthetic. If you live in the snowbelt or a lot of 'stop and go', change every 3000 miles and stick with the recommended viscosity for the time of year---synthetic, if it makes you feel better.

Don't misunderstand me here.  Synthetic lubricants are the top of the line and I highly recommend them where they are needed...they are just not needed in every application, IMO.
The analogy to fuel---if your car only needs 'regular' then money spent on 'premium' is wasted.

Rod

RE: Synthetic Engine Oil

I'll throw my two cents in, least I disappoint Evelrod.  The most important thing is regular oil and filter changes using quality components, as well as checking the oil regularly.  Any name brand oil must meet minimum automaker's standards.  Not changing the filter limits it ability to filter the oil for the entire second interval as well as instantly contaminating the new oil.  Oil never wears out, it's additives are consumed and it absorbs all the acids and dirt it can.  Running an engine low or too high on oil limits lubrication by a sheer lack of oil or the oil being whipped and foaming by contact with the chankshaft.  Now, petroleum based oil has some light faction molecules that boil off and heavy factions that form larger molecules (polymerize), this takes awhile.  Synthetics are essentially a base stock of one or two closely controlled molecules that resist those changes, so it comes in handy for extended (>6,000 mile) oil changes, temperature extremes or severe (heavy load, high speed) service.  Again, first do regular changes with quality components, check the level regularly, then look at the synthetics to see if they can be of use.  BTW, I use Mobil 1 and Puralator Pure 1 filters at 7500 mile intervals; not the highest/most expensive, but far from the cheapest.

Blacksmith

RE: Synthetic Engine Oil

Some synthetics (PAO's) are in fact hard on seals.  This caused problems years ago, but oil formulations have long been improved to correct for it.  Other synthetics (esters) can clean varnish from old sealing surfaces which has been blamed for leaks.  This is rarely a concern with reasonably-maintained vehicles these days.

There's no harm in running a new vehicle on synthetics from the get-go, but be aware that to get the full benefit from them in normal service (no towing or driving like a taxi-cab) you must have the courage to run at least a 10K mi change interval, which few US-market cars allow for warranty purposes.  I think you'd have to be pretty persnickety to walk away from three free oil changes . . .

RE: Synthetic Engine Oil

I admit my answer may be slanted, because I am an Amsoil dealer. In many cases, switching to synthetic oil on a high mileage engine wil find weak spots, and you will find oil leaks. Synthetic oli has a habit of cleaning up varnish deposits in older engines. In many cases, these deposits are actually keeping the oil from leaking. Amsoil suggests using their XL7500 oil in these instances, as it has less self-cleaning properties.
I switch all my vehicles to synthetic as soon as possible. I use the Amsoil guidelines for oil change intervals. My 98 Dodge Stratus has been using Amsoil Series 3000 0W-30 since 2000 miles, is now at 125,000 miles, using 1 year change intervals. Amsoil recoommended 35,000 or 1 year intervals. I do not put that many miles on the car. The filter gets changed every 6 months. The oil is clean, and there have been no issues with any wear related items on the engine (had a headgasket go & a water pump).
I run 10W30 in my old Saabs, also with 1 year intervals, and filter change at 6 months. I put approximately 12,000 miles a year on those. Again, no wear issues on those.
Many folks have been brain-washed into 3000 mile oil changes. I call it the "Mobil Myth". If you look in any new car's owners manual, you will be hard-pressed to find one that recommends 3000 mile oil changes. Mobil has finally knuckled under, and started making oils that they claim will go beyond 3000 miles. This is due to pressure from competition. Beleive me, they still want you to change at 3000 miles.
Synthetics keep your engine cleaner and more efficient longer, as it is chemically pure to begin with, rather than refined to an acceptable level. You will find that even if the oil does get dirty, you can clean it up by changing filters. With the currant costs of cars these days, I don't know why there is anyone that does not use synthetic oil. You can link to Amsoil from my website www.lubealt.com

Russell Giuliano

RE: Synthetic Engine Oil

Hi Russell.

I appreciate hearing your point of view, even though it is self admittadely biased (as is mine, I suppose).  I have a couple of comments...

125,000 miles with "...had a headgasket & a water pump"........only?

My old 77 Dodge went nearly 385,000 miles with "only" one water pump and a timing chain (changed at ~100k as a preventative measure...I don't trust the Al/teflon junk that the OEM were using at the time) on several brands of petroleum based lubricants.

Your advice about synthetics 'cleaning varnish deposits' is well taken, however, it is nowhere near the systemic problem that is commonly attributed to synthetic lubricants...based on my experience of the past ten plus years converting antique cars to Mobil 1...the most recent my original, two owner 1930 Ford, changed in Jan. 2000 at 100,000 miles and, currently at 122,000 miles with no appreciable concerns in the "leaking seal" department.  I went through all this in the 1950's when converting to "detergent" oils...Man I wish the  oil companies had used "dispersant" instead. Nearly all the problems in this area are from "sludge" deposits...moisture in the oil and lack of proper maintenance...is generally what I have found to cause it. Surprisingly, I don't see this problem very much these days...like I said, just about any oil today is far superior to (almost) ANYTHING I used in the '50's. (on my race engines and motorcycles I used Castrol 30R and 40R in the 50's and 60's... 'bean oil' and not petroleum based).

Changing filters in mid oil change interval...As long as at least one additional qt of oil is added in the process, I think the additive package will not totally disapate.  I still don't cotton to the idea, personally.  If the filter needs changing, so should the oil, IMO.  Actuall it works out that I change all my vehicles, save my wife's Lincoln (free dealer service), once a year as none but the motorhomes 454 bbc gets close to 6000 miles.  I  don't like extended interval oil changes for ALL applications...with oil analysis at 6000 miles, perhaps. Still not a general, blanket statement I am willing to condone, as I posted previously.

Brain washing?---Well, yes...they are dealing with the 'lowest common denominator' in most cases and that should not include the members of this forum---I so fervantly hope!

"...I don't know why there is anyone..."  I do.

Given the quality of virtually ever oil on the market today, my guess is that 90% of all automobiles will make it well beyond 200,000 miles sans lubrication related problems given normal use and adequate (indeed, even marginal) service no matter what brand or type of oil used.  Big statement?  Probably...I am used to sticking my neck out.  As I stated before, I use synthetic because of my 'perception' of ultimate quality for MY vintage and racecar applications.  Most all the rest of my stuff is still on Castrol.  Engine use in high performance, high heat conditions demand the best...usually a quality synthetic. I don't use Redline (probably the best race specific lubricant generally availabe, IMO) in my racecar because it's a bit out of my 'feel good' budget (I am retired and SSI provides the largest chunk of $$$ for my vintage race efforts) and, I don't use Amsoil because I have fallen victim to their agressive advertising in the past...I appreciate your more moderate approach, however, overt sales efforts is strictly 'verboten' in these forums.
Ultimately it comes down to what you get for your buck! I am all in favor of using the best one can afford.  I just don't confuse 'want' with 'need' if I can help it. winky smile

Rod

RE: Synthetic Engine Oil

Although I am a distributor, I never "push" the product. Oil opinions are too hard to change. They are the leader in Research & developement of synthetic lubricants, with all the others being followers. Too bad they picked a crappy way to bring the product to market.
As far as "only a headgasket & a water pump" please remember you are comparing a 77 Dodge to a 98.
The water pump bearing is most likely inferior quality, made in China, and the original headgasket was not engineered for the differences in thermal expansion between the aluminum cylinder head, and the cast iron block. The replacement headgasket was a mult-layered steel design, which seems to be holding up. Times change, so does production & engineering quality, all in the name of shaving off a few cents here & there. The other problem I had with this Dodge was when they went to "cab-forward" design, they gave no thought of beefing up the front brakes until a design change in 2002. I was getting approximately 15,000 miles per brake change. I actually got more life from the synthetic oil than the front brake pads.
Due to the expense of new vehicles, I now make sure I do not skimp on the sundry items that make these vehicles run. I use the most expensive oil, and I use either Mercedes-Benz anti-freeze, or now I can find Zerex G05. I do not mind the extra cost, as it saves me lots of time & money down the road.

Russell Giuliano

RE: Synthetic Engine Oil

>"--like I said, just about any oil today is far superior to (almost) ANYTHING I used in the '50's. (on my race engines and motorcycles I used Castrol 30R and 40R in the 50's and 60's... 'bean oil' and not petroleum based"<

Rod,
I've always thought that true castor oil is the "best" oil around, at least for film strength.  Not too practical for pass. car use, but it's required for many high-perf. 2 stroke model airplane engines.

RE: Synthetic Engine Oil

True enough at the time.  Synthetics have pretty much taken over, even in some of the methanol/nitro model fuels and certainly in all forms of motorsports.  The Castrol 30R and 40R that I used was the best race engine lulbricant and pretty expensive, even then and required frequent changes as it tended to 'gum up' things if left in too long.  I usually changed after each race weekend...sure did smell good...I can still smell it as I type this!!! An aside---"R" was the first oil I ever bought in a plastic bottle...leading edge stuff back then. I am not at all sure it is still available (I gave my last case of 30R to Don Vesco 20 years ago when he was still in Temecula).

When running methanol in my Bultaco, I used 5 gal to one pint of de-gummed castor oil.  Never had a problem at that mix.  I suppose it would still work today---for someone a lot younger than me...I'm too old for more broken bones.

All this is what I ment when I said "(almost)"---I'll bet that todays reclaimed/recycled oil at Wal*Mart is as good as most any top line  motor oil of 1955.

Rod

RE: Synthetic Engine Oil

Perhaps a point of interest- castor oil is an ester, which means it is a Group V on the base oil interchange rules.  This makes it a "synthetic" that is all-natural as well (!?!), and illustrates how slippery the meaning of synthetic has become.

Crankcase oils make inferior 2-T lubricants, and vice-versa.  I think model airplane engines usually employ an otto-cycle as well.  It may be that alcohol-fueled model airplane engines don't generate enough heat to activiate conventional AW chemistries, and this also may mitigate castor's serious varnish-forming tendencies as well.  In any case, it's hardly considered 'da bomb' these days for crankcase apps.

RE: Synthetic Engine Oil

I thought (2-stroke) model aero engines were usually compression ignition?

RE: Synthetic Engine Oil


One of the outstanding differences between synthetics and natural petroleum distillate base lube oils is precisely their distillation range. Narrow, ~30oC, for the synthetics due to their being almost pure chemicals vs ~ 200oC for regular extracted/hydrofinished base oils.

This characteristic (besides the additive and blending formulations) may help to explain their differing mechanical and thermal behaviour in engines.     

RE: Synthetic Engine Oil

>"I thought (2-stroke) model aero engines were usually compression ignition?"<

Some of them are.  They are true diesels that don't make much HP/cu. in.  But it "team racing" (F2C) it's amazing how far they can fly with so little fuel.

But the rest of 2 stroke model engines don't run on gasoline-they use methanol/nitro.  These fuels can use so much spark advance that it was discovered back around WW2 that a "glow plug" worked fine.  The glowing wire ignites the fuel far earlier than what gas would tolerate.

The really high HP model engines REQUIRE castor oil instead of "synthetics".

Interesting that methanol will dissolve large % of castor, but nitromethane won't.  But, when running more than ~45-50%NM if ~10% nitrobenzene was added it all mixed fine.

Then it was discovered that NB can cause cancer, so it fell out of favor.  They even had to take it out of Hoppe's #9!

RE: Synthetic Engine Oil

I have an old bottle of #9 and it smells quite different than the new bottle I bought last year.  Hmmmm, learn something new everyday.

Back on topic---I would find it interesting to poll the members that still don't like synthetics and their reasons.
I personally do not use synthetics in every case, as I have posted, but I do percieve them to be superior and cost effective in certain applications.

Rod

RE: Synthetic Engine Oil

>"I have an old bottle of #9 and it smells quite different than the new bottle I bought last year."<

The new stuff contains ammonia or some kind of ammonia compound.  NH3 is just about the worst thing to have around copper alloys.  I wonder if it has caused SCC of cartridge cases.

RE: Synthetic Engine Oil

I used to like synthetics a whole lot, and always used them... then at lunch one day, the head guy in a particular OEM's fluids department (guy who specs lubes and change intervals for that OEM) told me that his recommendation for the best engine life was that I should just use the cheapest "normal" oil of the recommended visc. grade and change it regularly (~3000mi), and not bother w/ synthetics, etc.  I still like synth oils, because I believe I get better fuel economy when using them (probably due to slower viscosity increase), but I'm a little less enthusiastic than in the past.

RE: Synthetic Engine Oil

Well, Isaac, we came at the solution from two totally different directions but, we do agree.
I use the synthetic for that little extra film strength in the race engine...and still change it after a max of two weekends...leave no stone unturned sorta deal, hey?

Bottom line, I have never had a bottom end problem traceable to the failure of the lubricating  oil I was using, never in 50 years!  Maybe I am too anal about all this?

Rod

RE: Synthetic Engine Oil

WOW! Ivymike, the cheapest? I have tried selling synthetic oil to municipalities in NJ, where I am told that they must buy through the NJ state contract. This is usually re-refined waste oil, that bears a disclaimer on the label "not to be used on new equipment". I only pay attention to the "not to be used" part.
This is the reason I don't "push" the synthetic product. Opinions on motor oil are very strong and varied. It is easier to get someone to change their political party.

Russell Giuliano

RE: Synthetic Engine Oil

Yes, the cheapest was his suggestion, by which I believe he intended to indicate that replacement frequency was of significantly higher importance for engine life than any advertised special formulation of the oil.  An underlying assumption, I believe, was that we were talking about typical bottled motor oils at a local auto parts store (where the cheapest is the $0.89/qt variety).  


RE: Synthetic Engine Oil

Regarding the original post questions -
I'd use the 3 free oil changes at the dealer, both to use what you paid for in the purchase price as well as flushing the engine and giving the rings time to seat properly.

Personal preference - I've been using Royal Purple for about 12 years mostly because the synthetic stays put on the bearings better the distilled dinosaurs when vehicles are not driven on a regular basis.

Sidebar: Hey Rod - remember the great debate on that swirl gadget for the air cleaner - turbo something - with all the alleged HP boost?  There's another one out that I saw at the PRI show last week that splits the throttle plates to induce swirl. The gear mechanism is huge. They had a patent and some innovation award. Think I'll keep the cash instead.

"If A equals success, then the formula is: A = X + Y + Z, X is work. Y is play. Z is keep your mouth shut."
-- by Albert Einstein

RE: Synthetic Engine Oil

"Swarups". They advertised those in the BMW motorcyclist magazines in the late '70's.

RE: Synthetic Engine Oil

sprintcar----"Tornado"...still selling to stupid consumers...old P.T. was right on...I hate stupid people...ignorance can be corrected with education, 'stupid' is life long and incurable!
Aside---What happend to that gal that was on your circuit?  All I read lately is on Katherene Legg and Donna Patrick from road racing.

To All...I have not been adding my standard tag line but, lest anyone forget...

Believe only half of what you see and none of what you read.

Rod

RE: Synthetic Engine Oil

Rod
I found the flyer  www.cyclocharger.com

I can just see this on my small block chevy Hilborn injection......

Ol' P.T.'s saying needs to be updated .. more like 10 born every minute today!

Erin Crocker ran with us for a few races. Nice girl, decent driver. Becca Anderson was here a year or 2 ago, just read that she got a World of Outlaw ride for 2006.  Thankfully the other female (nicknamed "The Weapon") retired before she killed herself or one of us.

I'm a crash test dummy for the HANS device now - they send you a neat t-shirt (current value $25000 in wrecked parts) if you make the Customer Testimonial page on their website. www.hansdevice.com
Mine's NOT the one going out over the fence - he got on TV while Speed Channel left 5 laps before I set the altitude record!

"If A equals success, then the formula is: A = X + Y + Z, X is work. Y is play. Z is keep your mouth shut."
-- by Albert Einstein

RE: Synthetic Engine Oil

Erin Crocker---I was quite impressed with what I saw on the telly.  Don't know about altitude records, my 2003 launch was only 30 feet up and 5.5 turns for a nose first finish...probably a record for a 65 year old driver in a Mini Cooper...$22,000 including a classic 30 second video!!!

Merry Christmas and sorry for sorta hijacking the thread.

Rod

RE: Synthetic Engine Oil

I think for my current vehicles any oil will work fine in the main and rod bearings and on the pistons.
My old engines have become troublesome due to valve guide wear, timing chain and gear wear, and gunk and varnish build up.

The latest SAE spec includes a minimum viscosity at a temp higher than the standard ~ 100 C, which make me think that's important. I'd like to think Synthetics' better VI means higher viscosity in hot spots like valve guides, and lower volatility means more (some) oil remaining there too.  I hope it makes my timing chain last forever too.

RE: Synthetic Engine Oil

Here are some oil suggestions from my experience. Don’t use too good of oil for the first several hundred hours of operation, or the rings may not seat well. Experience 1, 1981 Ford PU with 6 cyl. @100,000 miles with Delo 400, you could still see the hone marks, truck sold with 150,000 miles. 1987 Ford PU with 6.7 diesel, had to be re ringed from running Delo 400, ran Castrol 15-30 until sold with 150,000 mile. 1992 Ford PU 460 V8, used Castrol 15-30, change oil and filter every 5,000 miles, didn’t use a quart between oil changes, sold with 150,000 miles, seen at 250,000 mile still not using oil. We use a Yanmar L100 diesel engine in our pull through delimber, Union oil and Delo 400 cause the rings to not seat, and we have had to re ring some engines to provide enough compression to allow the engines to start.

RE: Synthetic Engine Oil

Ihave heard the "synthetic keeps rings from seating" argument many times, but never an explanation of how if true, changing to mineral oil for a time doesn't then allow them to seat.  Sounds a little cryptic to me.  Perhaps there was something mechanical wrong with the rebuild that the mechanic blames on the oil?

RE: Synthetic Engine Oil

I agree - I've got a bit of experience with piston & ring design, and I've yet to see a case where "ring seating" ("seating" being mostly the reduction of Rpk on the liner) failed to occur because of an oil selection.  

I have seen all sorts of problems described by mechanics as "rings not seated," ranging from unexplained white vapors from the CCV (occasionally due to a turbo problem) to drivers' reports of high oil consumption to "dusted" rings.  It is often the case that replacing the PRL sets is the third thing a mechanic tries when fixing an unexplained problem, that it's done in conjunction with other repairs, and that the description he writes down is "rings not seated."  The efficacy of such repairs is (as you might expect) a crapshoot.

RE: Synthetic Engine Oil

As far as I know, several of the up market Euro mfgrs. use synthetic exclusively, break in or no.

I still start up on non synthetic, in reality, to flush out all the 'junk' as much as anything.  I did start one engine a while back on Mobil 1 (inadvertantly) and it ran in the same as any other, leaving me to ponder the inherited "wisdom" of the "never use synthetic to start as it will not allow the rings to properly seat" logic.

I have reached a crossroad in my lubricant usage...I have switched to using race specific motor oil--- Red Line synthetic in the race engines...hang the expense.  Perhaps you really can teach an old dog...

Rod

RE: Synthetic Engine Oil

Like Rod, I always use mineral oil for the initial start of a new race motor, typically Valvoline Racing 15w40 or 20w50 if I can find it.

While the jury is still out on the ring seating issue, I like to clean out all the junk (stray silicone, lint, bugs, the neighbor's cat) that somehow finds its way into the engine during assembly. After a filter change, I typically run one or 2 races on the oil then switch to the Royal Purple synthetic.

"If A equals success, then the formula is: A = X + Y + Z, X is work. Y is play. Z is keep your mouth shut."
-- by Albert Einstein

RE: Synthetic Engine Oil

Ditto

I have started new engines on synthetic with no problems.

Also I normally start on mineral oil, and run in the cam and bed the rings, then change oil and filter. Reason for mineral oil is economic only as 30 min fast idle and 1 or 2 minutes of short burst power runs is a very short service interval for the oil, hence it is a waste of good synthetic oil.

Regards

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RE: Synthetic Engine Oil

My Ford and Yanmar experiences are with factory new engines. In all of the Yanmar engines the top 2 rings are for compression and the third is the oil control. There is excess oil building up on the compression rings which burns, leaving a gummy material that ultimately causes the ring to stick and not hold compression. The one running Union only had about 500 hours, and I had to break the rings to get them out of the grooves. These engines run at 3,000 rpm 6 to 10 hours per day at varying load.

RE: Synthetic Engine Oil

I would consider "ring sticking" to be an entirely different phenomena than the lack of "ring seating."  The lube oil you use can have a very significant effect on the rate of lacquer and/or carbon deposit formation (and thereby ring sticking).  Certain popular brands even have huge variability batch-to-batch for the same oil type.  I would suggest that if you find an oil brand/type that works well in your "sticky" engine, you stick with it, synthetic or not.  

RE: Synthetic Engine Oil

Another favorite complaint is that synthetics are so "slippery" that they can cause roller- or ball bearings to slide instead of roll leading to ruined engines.  Besides sounding incredible, what is never explained is how a lubricant that reduced the traction in such bearings to such an extent that they were essentially behaving as journal bearings could possibly lead to failure?  It's so good that it's bad?!?  Does it pass the bogeyman test?

RE: Synthetic Engine Oil

Roller or ball skidding is more common with grease, but can happen with oil if there is too much clearance between the components.

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