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Oil (again)  
Oil (again) - THe Growler
Prowling round the car supermarket where I live and looking at motor oil yesterday, I note the following (I have made the sterling conversion at today's rate for the sake of clarity).

On the shelves Mobil 1 sells for £4.52/liter. Pennzoil, Quaker State, Valvoline, Caltex Havoline, Shell and Castrol brand synthetics sell for (+/-within a narrow range) £2.76/liter. From my local gas station Petron (that's the Philippine national oil company 40% owned by Saudi Aramco) synthetic sells for £2.58/liter. (For the sake of comparison, Caltex fossil 15w/40 sells for £1.41/liter). All rated API SL by the way.

Question: why is Mobil 1 more expensive for apparently a similar product and why would I buy it when there is a wide choice of cheaper and apparently identical synthetic oil alternatives in terms of specification?

Next question: what is the point of semi-synthetic oil? It appears to be something and nothing. My Harley Service Manual demands semi-synth in its transmission yet I have run it on Pennzoil 80w/90 fossil prior to changing to HD's own semi-synth a few months back and noticed no difference whatsoever (i.e. engaging first from neutral still frightens small dogs and old ladies hehe).

I await enlightenment.

Tags: technical issues buying a used car oil maintenance and servicing

Oil (again) - CMark {P}
This isn't enlightenment, G., but might be interesting.

I was initially running my diesel G-wagon on Mobil 1 (which I had bought in a 60 litre drum direct from their oil depot in the Europort, Holland).

After 3 years the car was back in Europe and I started going to a well-known independent G-wagon specialist. They were using the M-B recommended Shell semi-synth. When asked why they were not using fully synth, they said that, as long as one follows the recommended oil change intervals, they had seen no advantage in using the more expensive fully synth.

They had neither seen nor heard of any lubrication-based failures with this correct semi-synth even in competition use and star-ship mileages. "Just be sure to change it regularly, according to the schedule".
Oil (final answer?) - eMBe {P}
Growler, thanks for asking the question as it may help expose/nail the myth of 3000 mile oil changes. Apologies for a long answer:

Q1. I do not know why Mobil1 should cost more than the other synthetics. (note: Mobil1 and some others too are not true synthetics anyway). I suppose it is just marketing hype to charge more to get its perception up as a super/special brand.
Q2. Some modern engines with tight tolerances must be run on special synthetics. Older high-tech engines will be OK on semi-synth, and really old (10 years plus) probably will need no mor than old-fashioned mineral oil.

The key to your question is the frequency of oil changes. Modern long-life synthetics can last very very long. Let me quote from some technical papers that debunk the myth of 5000 mile or annual oil-changes:

".. set the record straight and clarify that the idea of extended oil drains is not just something dreamed up by snakeoil salemen and the companies that supply their products ...
...many of the companies and individuals that support the viability of extended drains are not going to receive any significant benefit from the implementation of extended drains ..
...The people who are going to tell you extended drains are not possible are either in the business of selling oil and don't like extended drains because they eat into their profits, or they are people who have used conventional oils and conventional drains for years "without a problem", "so why switch now?" ...

...The field trial results also document the performance of a premium fully synthetic engine oil at four times conventional oil drain intervals. Engine inspections conducted after 500,000 test miles confirm that the extension of oil drain intervals with premium diesel engine oils has no negative impact on engine durability.
1998 SAE Paper 982718 - "Extended Oil Drain Performance Capabilities of Diesel Engine Oils" by S.M. Letter, K.J. Kelly and M.A. Ragomo of Mobil Technology Company, R.C. Morrow of Mobil Oil Corporation and D.S. Nycz, G.M. Karl, D.F. Gullet, R.G. Dussault, B. Butler and T.H. Becker of Caterpillar, Inc.

...The field trial results also document the performance of a premium fully synthetic engine oil at four times conventional oil drain intervals. Engine inspections conducted after 500,000 test miles confirm that the extension of oil drain intervals with premium diesel engine oils has no negative impact on engine durability.
1998 SAE Paper 982718 - "Extended Oil Drain Performance Capabilities of Diesel Engine Oils" by S.M. Letter, K.J. Kelly and M.A. Ragomo of Mobil Technology Company, R.C. Morrow of Mobil Oil Corporation and D.S. Nycz, G.M. Karl, D.F. Gullet, R.G. Dussault, B. Butler and T.H. Becker of Caterpillar, Inc.

......engine oil servicing is still recommended in the range of 3,000 to 7,500 miles in the North American market. Extension of oil change interval recommendations beyond 15,000 miles is now being discussed within the international automotive industry. This paper documents the development and testing of new synthetic engine oil technology under extended service intervals of up to 25,000 miles or three years.
...In vehicle field tests under both high and low mileage accumulation rates, premium quality low viscosity synthetic engine oils provided excellent durability, engine wear protection and cleanliness under severe extended oil drain interval conditions.
1998 SAE Paper 981444 - "Advanced Synthetic Passenger Vehicle Engine Oils for Extended Oil Drain Performance" by R.J. Bergstra, W.A. Givens, W.L. Maxwell and W. H. Eichman of Mobil Technology Company.

... Below is just a fraction of the available articles/studies focused on the effect of oil & filter quality/type on oil drain intervals. Just head over to the SAE website and do a search for the article number ..
982718 : Extended Oil Drain Performance Capabilities of Diesel Engine Oils
981368 : Doubling Oil Drain Intervals - The Reality of Centrifugal Bypass Filtration
2000-01-1822 : Evaluation of Oil Performance Using the Tu High Temperature Engine Test With a View to Extending Oil Drain Intervals
981444 : Advanced Synthetic Passenger Vehicle Engine Oils for Extended Oil Drain Performance
2000-01-1992 : Development of High-Performance, Heavy-Duty Diesel Engine Oil to Extend Oil Drain Intervals: 5w30 Fully Synthetic Oil Containing Modtc
981443 : Extended Oil Drain Intervals - Conservation of Resources Or Reduction of Engine Life (Part II)
981448 : Used Oil Analysis and Study of Oil Drain Period in Gasoline Engine
2001-01-3545 : The Effect of Engine Age, Engine Oil Age and Drain Interval on Vehicle Tailpipe Emissions and Fuel Efficiency
2001-01-1898 : Oil Quality With Oil Age in An IDI Diesel Passenger Car Using An On-Line Lubricating Oil Recycler Under Real-World Driving

If that is not enough, here are some more links that may enlighten you:
www.chris-longhurst.com/carbibles/engineoil_bible....l
www.mg-sportcars.co.uk/Motor_Oil_FA_Questions.htm
www.practicingoilanalysis.com/article_detail.asp?a...n
www.practicingoilanalysis.com/article_detail.asp?a...s
Oil (final answer?) - Bob the builder
Excellent, informative, technical post Embe. Thanks. However, ordinary run-of -the-mill DIYers like me don't know the supposed ins and outs of these matters. My last three cars have all run exclusively on Mobil 1. I have had no problems at all with any of the cars. My current 2.0l Carina has just turned 80000 trouble-free (touch wood) miles. I change the oil 3 times a year no matter what. I continue to use Mobil 1 because (a) I get it at less than £20 a tub in French supermarkets (b) the million mile BMW ran on it and (c) no-one seems to have a bad word to say about it. But, the point is this ; unless I totally strip the engine down I wouldn't KNOW if it works well, and even then I wouldn't be able to prove it one way or the other !. My wife's Focus and my Fazer bike run on it too - no probs. Finally, it always strikes me as odd that motorists seem very happy to fill tanks up with petrol at £50 a fill once, twice or more per week, and then baulk at changing oil at probably (in my case) no more than £25 per change (diy) , three times a year.
Oil (final answer?) - eMBe {P}
>>>> on it too - no probs. Finally, it always strikes me
as odd that motorists seem very happy to fill tanks up
with petrol at £50 a fill once, twice or more per
week, and then baulk at changing oil at probably (in my
case) no more than £25 per change (diy) , three times
a year.

>>

You've got it in one. If you can afford it, or have the time, and/or inclination, there is no harm to your engine in changing your oil every 1000/3000/5000/10,000 miles or annually as it suits your needs. (The only harm possibly may be in wasting precious resources, but that is a diferent topic). There is no magic in these mileage or time figures. The best guide to deciding when to change oil is to do the test given in
www.practicingoilanalysis.com/article_detail.asp?a...s
Oil (final answer?) - CMark {P}
Great posting eMBe.

However, the business card spot test link you recommend is less than helpful.

I have just carried one out on my Jeep which has not had its Mobil 1 changed for 10 months and 11,000 miles. Yet the spot on my card looks nothing like the one in the picture.

Your link provides no help in interpreting the reults of the test it describes. In fact, you have to buy his book to find out more.

I would say this link contributes to, rather than debunks, the early-oil-change myth by planting worries in the minds of drivers even when using fully synth. (Of course, they could set their mind at rest by buying the book...)

Oil (final answer?) - J Bonington Jagworth
"the spot on my card looks nothing like the one in the picture"

Are you sure you've got the right sort of business card? :-)
Oil (final answer?) - CMark {P}
LOL, JBJ. Of course, I haven't got the right sort of business card but that is my whole point. Too many variables. The fellow is using scare tactics to sell his book. Really unhelpful.
Oil (final answer?) - J Bonington Jagworth
"The best guide to deciding when to change oil is to do the test..."

Now that I do agree with, but it rather pulls the rug from under the other learned papers, don't you think? The Oil Analysis author regards 5000 miles as extended and prescribes a double oil and filter change as a result!

The one thing that extended wear tests do not simulate is real life usage, especially short journeys and lots of cold starts. I know I've mentioned it before, but Irv Gordon, the 2-million mile Volvo owner, changed its oil every 3000 miles...
Oil (final answer?) - eMBe {P}
Oil Analysis author regards 5000 miles as extended and prescribes a

Well, this guy does have a driving habit which means he probably does 2000 miles a year, and he did "more than 5000 miles" and he does say ".... Cause and Effect
Why did this happen? The main reason was my driving habits. I?m frequently away on business so my car sits in the garage most of the time. When I do drive, it?s usually short distances (typically 3 to 4 minutes to the office). This causes moisture to build up in the crankcase (perhaps as much as 20 percent), which in turn, causes additive distress, loss of dispersancy and sludge. The condition was compounded by the fact that it was January (cold driving conditions hold moisture longer in the oil). ...."

The one thing that extended wear tests do not simulate is
real life usage, especially short journeys and lots of cold starts.


The SAE technical tests I referenced did do so.

As for the test, note:
"....If you see undispersed soot, characterized by an inability of the soot to wick outward into the card stock, this mayindicate that you need to change your oil more frequently. In contrast, if you see no structure (sticky centers, rings, etc.) on the card, you might consider extending your oil drain. Keep in mind: The optimum drain interval may change by season, age of the car and quality of filtration. Also, other oil properties may become impaired before dispersancy is lost. ..."
Oil (final answer?) - J Bonington Jagworth
I hear what you say, eMBe, and I applaud your original post for its thoroughness, but you are challenging deeply held views here!

I agree that the Oil Analysis guy is hedging a bit, but he's American and doubtless sees lawyers round every corner. However, when he says: "The optimum drain interval may change by season, age of the car and quality of filtration" he is exactly right. He could also add journey length and frequency and annual mileage, so any simple guide to oil condition is useful, even if only rough.

Manufacturers' recommendations do not take these variables into account, and are, I suspect, designed to maximise the service interval. Very few people keep new cars until they die of old age, and are unlikely to blame the occasional failure on oil change frequency. In any case, the manufacturers are not really interested in making them last, just as long as they don't get a reputation for the opposite!
Oil (final answer?) - J Bonington Jagworth
"I applaud your original post for its thoroughness"

But only two cheers, as I've just found the source of most of it:

www.motor-oil-bible.com/index-test9-new.html

and what do you know - he's selling a book, subtitled "Exposing the Myth of the 3,000 Mile Oil Change"!

Oil (final answer?) - eMBe {P}
JBJ: Thanks for that link. The quotes I gave were from an e-mail sent to me an industrial- chemist friend. They may well originally be from the source you quote, or your source may have got his from where my chemist friend got his info.
Oil (final answer?) - eMBe {P}
>>>> no matter what. I continue to use Mobil 1 because (a)
I get it at less than £20 a tub in French
supermarkets


Bob - Which spec is the French Mobil1 ?

P.S. to JBJ - no comment, as I am not in the mood to respond to pedantic nit-picking. ;-)
Oil (final answer?) - Bob the builder
Well, it used to be 10 - 50 but the last lot I bought three weeks ago was 0 - 40. Think the 80K Carina will notice ? !!!!
Oil (final answer?) - J Bonington Jagworth
"Some modern engines with tight tolerances.."

Ettore Bugatti made his engines (in the 1920's) with tolerances so close that they didn't need gaskets. Don't see much improvement lately...

I would agree that metallurgy has improved since then, but, all things being equal, frequent oil (and filter) changes must be better than infrequent ones...
Oil (final answer?) - J Bonington Jagworth
"really old (10 years plus)"

That's new in our house! But if you think it's old (and the authors of the supporting literature would doubtless agree with you) then your view of engine life is also different. Life is not just mileage, it's standing around with everything slowly oxidising!
Oil (final answer?) - THe Growler
Yes I've done my homework on types of oils and their relative features and benefits: I even gave a talk on it at my bike club last year, but.....

If marketing hype is all it is, then if I want to buy synthetic I can just go for the home-grown oil company brand at a 45% price saving, then. Mobil 1 is a rip-off on that basis. I didn't even mention proprietary makers' oils either. I was in the Honda parts shop yesterday and saw their Honda synthetic is even more expensive than Mobil 1. But I bet it's probably made by Shell: certainly Honda is in the business of making cars, not refining and packaging engine oil. But if I took my car in there for a service, guess what they'd fill it up with.

Harleys do this with their 360 oil. Everyone knows it comes from either Citgo or Sunoco (run of the mill US oil companies) depending on what day of the week it is, and is allegedly recycled anyway, yet the Motor Company proclaims dark things will happen if you use anything except HD Oil, which, naturally, for its "superior" quality, costs 50% more than regular gloop.
Needless to say I don't and they haven't.

But then what is the purpose of semi-synth? Why not either stick with the fossil half of the semi (and save money) or go all the way (and spend money) to get the purported full synth benefits?
Why a half-way solution?

Oil (final answer?) - Dr Rubber
G,
I was talking to a bloke from Ford's research place a couple of years back. He was saying Ford do a lot of research into the "right" oil for a car, and their own brand oil is based on this research. I don't know if this means they check generic oil against a spec or what, but he recommended using their oils. This I did, but mainly because it was one of the cheapest 10W30 oils I could get.
I can't help on the semi-synth side though. I use it, as VAG's oil is semi-synth.
Joe
Oil (final answer?) - CMark {P}
Big G asked: "Why a half-way solution?"
Answer: because that is all that is needed.
Oil (final answer?) - J Bonington Jagworth
"Why a half-way solution?"

Because there's a market for it, I imagine. Perhaps it provides a comfort zone for those who would like fully synthetic, but baulk at the price. Would it help if you regarded it as ordinary oil with a large amount of synthetic additive? :-)

BTW, not being a chemist, I'm a bit puzzled by the origins of synthetic oil. It still comes from the refinery, doesn't it?
Oil (final answer?) - Dr Rubber
Again I'm not a chemist, but "mineral" oils are most likely based on a certain distilate from the crude oil (like petrol, kerosene diesel etc.).
"Synthetic" oils are manufactured, I would guess from monomers, to give the required molecule. This is likely to give better control over contaminants, molecular weight (number of atoms), chain branching etc. This allows the chemist to get the properties spot on for their oil (one reason why mobil 1 is so expensive?).
So I guess you are right, all oils come from a refinery, but some by a more direct route than others :-)
Joe
Oil (final answer?) - Ben {P}
This is all rather badly written sorry, just not got time, and all IMHO:

Growler- are the synthetic products in "semi-synthetic" oils not there just to maintain viscosity as the oil warms up?

When i looked into this, i remember concluding mobil 1 is better than some of the other oils. But its all a matter of dirt. If the next best range of oils are %50 cheaper or whatever it would not be worth using mobil 1- difference will be minimal.

I had exchanges with learned Americans on this subject. some with chemical engineering backgrounds. Some of them ran 15k mile oil changes using mobil1, with oil analysis for example. At this point the oil still had not degraded. But one striking general trend was that all these guys had had to change their oil filters at around 5k mile intervals. So, in real world situations, the oil can fill with dirt, yet not have degraded. When i have been using full synthetic oil and been tight for cash i have just changed the oil filter in the past.

Even synthetic oil uses viscosity improvers- which over time degrade. Mobil 1 0w-40 for exampleis remarkable in that from the base temp viscosity test (40c) to the normal running temp test (around 100c i think) its viscosity changes by a factor of only 7 or 8 if i remember correctly. Now these "long life oils" i presume have less viscosity improvers, allowing a longer drain interval. But this means poorer viscosity stability (IMHO), i presume this will be shown in the viscosity index figures- does anyone have the specs? Racing oils etc are more likely to have a far more limited viscosity range. High performance oil manufacturers red line proudly cliam they use less additives as theirs oils perform far better under high stress conditions. Its all a case of swings and roundabouts. Climate should play a very big part in choosing oil.

One problem with mineral based oils degrade more quickly. As they do so their viscosity increases.

I still think if you do plenty of short trips changing oil after 5-7k miles is not a bad idea. For those doing 20k plus a year 10k mile changes should be fine. On synthetic oil, of course.
Oil (final answer?) - THe Growler
>>>>>I had exchanges with learned Americans on this subject. some with chemical engineering backgrounds. Some of them ran 15k mile oil changes using mobil1, with oil analysis for example. At this point the oil still had not degraded. But one striking general trend was that all these guys had had to change their oil filters at around 5k mile intervals. So, in real world situations, the oil can fill with dirt, yet not have degraded. When i have been using full synthetic oil and been tight for cash i have just changed the oil filter in the past.
===========

This is the second time I've come across this philosophy and it's interesting. I post on another US forum which is bike-related but came across a thread which included some unusual comments from the owner of a small US trucking company.

He runs Kenworth semis, which have a Cummins 22 litre diesel and if memory serves, need 8 or maybe more gallons of engine oil. He claims to run the synthetic oil for 100,000 miles between changes, but changes the filters religiously every 20,000 miles on the grounds the filters clog yet the oil does not degrade. His trucks are sold on after 2 million miles using this method to a firm in Canada which reconditions them and exports them. When the engines are torn down for inspection, wear is claimed to be minimal and had they not been opened up, would be good for many more miles.
Oil (final answer?) - Andrew-T
G - you are promoting a routine where filter is changed more often than oil. There was a time (not so long ago) when (at least for petrol engines) it was the opposite. Is this simply a reflection of saving cost on the more expensive component? If the messy operation is being done at all, may as well change both? There will always be penny-pinchers I suppose ...
Oil (final answer?) - Vagelis
Great presentation, eMBe!

I think engine oil and engine run-in are two of the most controversial issues discussed between motorists.

I have always based oil choice on three major factors:

1. Manufacturer recommendations: mainly the viscosity range.
2. Engine: If it has 16 (or more?!) hydraulically-controlled valves you have to use high-quality oil, which mostly means synthetic.
3. Ambient temperature: in summer I tend to use something like 15w50 (we commonly have 40C here!) and in winter 10w40-ish.

Following these guidelines never caused me a problem for about 10 years now, plus the oil always comes out black and well worked.

You mentioned that the mobil 1 is not a true synthetic oil. Do you know of other oils that claim to be but aren't?

Vagelis.
Oil (final answer?) - eMBe {P}
To see photos/results of the following test
Group A, Unit 100: Control, Petroleum oil, 3,000-mile drain interval
Group B, Unit 076: AMSOIL, 6,000-mile drain interval
Group C, Unit 070: AMSOIL, 12,000-mile drain interval
Group D, Unit 074: AMSOIL, No oil changes, 60,000-miles

go to www.searchforparts.com/important_articles/amsoil_t...l

Amsoil oil-product specs are at
www.amsoil.com/products/motoroils/index.htm

Vagelis:
You mentioned that the mobil 1 is not a true synthetic
oil. Do you know of other oils that claim to be
but aren't?


The Chris Longhurst oil-bible (link given above as well as in HJ's FAQ's) lists some of these.

Other Q's:
As for how mineral and/or synthetic oils are made, again Chris gives an summary. The best illustration I have come across is at
www.castroljapan.com/eng/useful_aboutoil_basics.sh...l

Also, look at the following sites -
www.bobistheoilguy.com/ (everything you ever wanted to ask)
www.castroljapan.com/eng/useful_aboutoil_grades01....l
www.infineum.com/information/viscosity.html
www.acea.be/ACEA/20020618PublicationsOilSequences....f

For Mobil1 grade 0-40: tinyurl.com/mvlu
For other Mobil1 grades: tinyurl.com/mvm5
Oil (final answer?) - Ben {P}
Notice in the taxi example, the oil filters were changed at 12k mile intervals (5 times) during the test. And for the milleage covered there would not have been many old starts, so although a useful test it certainly wasn't average. So, as i said, the limiting factor on these drain intervals isnt so much the oil but the filtration systems.
It is still a fact though that the more you change your oil, the longer the engine will last.

So eMBe- how often do you change your filters?

Oil (final answer?) - CMark {P}
eMBe, re-reading my posts above I think I might have been a little abrupt. I do applaud your postings here which add considerable value by bringing the together some weighty references on this subject that Vagelis rightly highlights as one of the most contentious technical issues facing the modern motorist.

The Internet provides unprecedented access to information. However, I am a natural cynic when faced with advertising masquerading as fact. This resulted in my sceptical review of the business card oil test, notwithstanding the fact that do-it-yourself oil analysis is an intriguing prospect.

Some of the links are already familiar particularly the well-balanced article by Chris Longhurst.

I have now had a look at promotional article by Amsoil, Testing with Taxi Cabs. Potentially interesting even for 1984. But the report does have a few discrepancies and even 3 spelling mistakes ("foundly", "inteval", and "desribed" - surely, even excusing dodgy Yankee spelling this is an error?). We all make typos [ahem] but three in an advertising piece?

What do those valve photos tell us exactly? Can someone explain what oil quality has to do with the build-up of carbon deposits on the back of valves?

If you look in the graph entitled N.Y.C. Field Test Deposit and Wear there is an error - Group B is listed as having a 3,000 mile oil change and yet previously Group B is described twice as having a 6,000 mile change.

And why include values for rust deposits when they are 100% for all Groups? It does not add any value and looks to me that they did not have any other statistic to support the superiority of their product.

All this points to a disappointing lack of rigorous credibility.

Picky, picky, picky. Yes, I might be missing the point here but we should not confuse a sexed-up quasi-technical report with research facts. We are often spoiled in the BR with postings from technical experts and persons with vast hands-on experience so we have a right to be fussy.

Do we not?
CMark
yesterday I couldn't spell engineer, now I are one.
Oil (final answer?) - wemyss
Chatting to a haulage contractor a while ago and we got on to the subject of oil changes.
They have previously changed their oil on their fleet of HGVs at 50.000 miles.
However he says the latest Mercedes have a 100,000 mile specified change using a specified oil.
He said that whilst they use up their existing stocks they will continue the 50K and then go on to the 100K interval.
Personally the habits of a lifetime makes me continue with 5000 mile oil changes but are they necessary?.
Of course the HGVs have a much larger oil capacity, lower revs and more constant temperatures but even so 100,000 miles makes me believe that we are probably over cautious, but I will continue for no other reason than that?s the way I?ve always done it.
Oil (final answer?) - eMBe {P}
CMark: I fully understand your scepticism - that is a consequence of the Mutton Hymnchoiry typified Britain we live in today.

But it is worth noting what Amsoil officially told Chris Longhurst :
"... I've been contacted by Amsoil themselves and asked to point out the following:
Amsoil do NOT produce or market oil additives and do not wish to be associated with oil additives. They are a formulator of synthetic lubricants for automotive and industrial applications and have been in business for 30+ years. They are not a half-hour infomercial or fly-by-night product, nor have they ever been involved in a legal suit regarding their product claims in that 30+ year span. Many Amsoil products are API certified, and ALL of our products meet and in most cases exceed the specifications of ILSAC, AGMA etc..... Their lubricants also exceed manufacturers specifications and Amsoil are on many manufacturers approval lists. They base their claims on ASTM certified tests and are very open to anyone, with nothing to hide. .... "

So there. Take it or leave it.

My own credentials: taught by Professors Thring, Langer and Braithwaite. Suffice to say those in the know will know. I have no connection with the motor or oil industry. I do however frequently talk to chemists whose full-time job is to sample fluids including lub-oils in major industrial applications.


Oil (final answer?) - Ben {P}
so eMBe, what is you advice regarding which oil to use, when to change it and when to change the filter?
Oil (final answer?) - No Do$h
So there. Take it or leave it.


Oooh, thanks! You mean we really get a choice all of our own? Without your guidance? How will we cope....

Actually, I rather liked that. The number of times I've wanted to finish a post on a similar vein.....

What would really help here is a brief synopsis that the majority of the users of this site can follow, rather than reference to detailed research that means little to the man in the street. I can't offer any expertise on the subject as my own experience of oil changes tends to be of the "£26 for filter and semi-synth and I don't have to get my hands dirty? I'll 'ave it!" variety. About once every 6k, more on the prevention is better than cure basis than on any scientific judgement.

eMBe, you appear to have a wealth of research material at your fingertips. If you can find a way of passing this on in a manner that will help the many, I for one would be hugely appreciative. Kwik-fit may not thank you if the answer is "don't need to change your oil so often if you do that many miles", but my bankmanager will.

ND

Oil (final answer?) - eMBe {P}
>> So there. Take it or leave it. Oooh, thanks! You mean we really get a choice all of our own? Without your guidance? How will we cope.... >>


ND: I was typing a bit late in the night, and some words got left out in the editing - it should have said " So there, the implied message from Amsoil to Chris Longhurst is 'Take it or leave it' "
What would really help here is a brief synopsis that the
majority of the users of this site can follow,


Brief Synopsis - which by definiton will always have omissions and exceptions, and is my personal view only:

1. If your car has a service interval indicator (modern BMW, Audi, etc.) use that a guide. If your engine uses long-life synthetic oil, you can go another 1000miles/1month beyond the "service due", it won't harm your engine. The Audi web site
www.audi.co.uk/customer/servicingoption.jsp
guidance on this is spot on "...There is no predetermined mileage for a service. Depending on how you drive, the interval will be up to 19,000 miles /24 months for petrol engines, up to 22,000 miles/24 months for the V6 TDI diesel and up to 30,000 miles/24 months for 3 and 4 cylinder TDI diesel engines. ..."

Audi or BMW dealers have nothing to gain from filling expensive oil in your sump and then telling you you need not change the oil for another 2years/20,000 miles.

2. If your car is "non-cat" "old-technology" of the pre-nineties era, you are likely to be on mineral-oils. Then change oil every 6 months or 5000 miles - whichever comes first.

3. If your car uses semi-synth, then change oil every 12 months or 10,000 miles, whichever comes first.
These are conservative figures on the principle "prevention is better than cure", and you can easily allow a tolerance of 20% on these mileages/time-intervals without any noticeable or significant harm.

JohnS who occasionally posts on the technical forum (and who has experience of "engines" costing £multi-millions ) has indicated that he does an extra oil change but allows his filter to clog-up, in-between dealer services, to give better filtration. I respect his opinion.

>> for one would be hugely appreciative. Kwik-fit may not thank
you if the answer is "don't need to change your oil
so often if you do that many miles", but my bankmanager
will.


Actually, Oil changes at K-F are very very reasonably priced.

As I said in a post above, there is no magic in 1000/3000/5000 or other such numbers. You can choose to cut the cloth to suit your wallet and convenience. Just check your oil-levels regularly, and check its condition visually. If you miss your routine for some reason, relax, no harm will have been done.

Exception: If your car is prone to forming "mayo", then 3000 mile (or even 2000 or 1000 mile) changes are a must until the problem is eliminated. For that sort of frequency of oil-change, if you are using mineral oils, Wilkinson do 5 litres for less than £3.

As pugugly says about the law, so do I about engineering:
"The above are just my opinions, but not advice".

P.S. - there have been hints that if a person trying to sell a book says something, it should be taken with a hefty dose of salt. Well, remember that HJ sells many excellent books, including "Motoring Answers".

I am away for the next 7 days, so if I don't reply, it is nothing personal!
Oil (final answer?) - eMBe {P}
While answering martin's "oil-change" query on another thread, I came across the French Kwik-Fit chain, know over there as "Speedy".

www.speedy.fr/speedy/fr/vidanges1.htm

Their web has an illustrated table of oil service intervals dependent on the age of the car. At those type of prices, (not all that different to UK kwik-fit and National), it should be worth following their schedule.
Oil (final answer?) - THe Growler
Well! I started this out by wondering why Mobil 1 cost more than other apparently similar brands of synthetic oil. 30 odd posts later I'm still wondering, although along the way I've learnt that NYC taxis only have 229 CID V-6 engines, (that explains why those non-English speaking Somalian cab drivers are so hacked off all the time), that semi-synthetic seems to be an orphan in a sidetrack, and (DUH?) someone actually believes letting their filter clog up makes it filter better.

NOW, let Big Dadi tell you the best reason of ALL for regular oil changes. In the Philippines absolutely every gas station has a lube bay which is spotlessly clean where you can just rock in and get your oil changed, your wheels realigned, your tires replaced und so weiter, without so much as a by your leave.

My local has all this plus a nice little sitting room with a TV and DVD with a selection of movies, today's paper and a coffee machine. The delightful Melissa who lords it (should that be "ladies" it) over all this fusses around a can be persuaded to bring me a beer from the mini-shop which is again part of all our gas stations, to enhance my oil change experience.

Jenalyn on the cash register is also a saucy little flirt like so many of her countrywomen so that helps pass the time as well while Rico the mechanic hoists the old beast (this is the hack used for off days) up on the lift and does the needful. Having finished that, new oil, sump plug torqued and checked for leaks he then takes it outside and washes down the engine for good measure. Cost last Tuesday inc 1 beer and tip Philippine Pesos 804, call it 9 quid.

Thus I certainly subscribe to the therapeutic and mechanical benefits of frequent oil changes. Much more fun than bunging in synthetic gloop and flagellating myself that I'm doing the right thing by waiting 20,000 km before visiting Melissa again. But wait a minute, I haven't had the wheel alignment checked for ages........


Oil (final answer?) - J Bonington Jagworth
Funny - it's not like that at National Tyre Services here :-(

As for "someone actually believes letting their filter clog up makes it filter better", I couldn't agree more. What IS that all about?!
Oil (final answer?) - Ben {P}
eMBe i cant believe you can reccomend someone to put that £3 oil in a car. I used the stuff tesco i think sell. My car got to temperature on my drive, the tappets started rattling like mad, so i drained it. It came out like water, and it was supposed to be a 20W-50 grade. Check very carefully on the bottle of these cheap oils to make sure it has met all the relevant quality standards. Whatever you use dont use the formula 1 branded oil in your car, changing the oil with this stuff will do far more harm than if you had just left the old oil in.

I think the condition of the engine should have some prominence. The more worn the eninge the more often oil changes will be required.

Growler: from all that i have read, i would say some experts believe Mobil is very slightly better than some alternatives. So with the price differential you are experiencing, deffinately not worth the extra cost. In your climate if i wanted the ultimate protection i would probably go with Red Line oil, or similar type synthetic with fewer viscosity improvers. Its just not fair you can have you car fettled like that for £9!
Oil (final answer?) - Dr Rubber
I think oil type/viscosity etc boils down to what car you have. I once had a Morris Marina (hides in shame) that did 50 mpg (oil not petrol). Needless to say I shoved the cheapest stuff in I could find, and changed the filter every six months.
My old ford escort (CVH) got the recomended Ford oil changed every six months/6k. (15ukp + half hour)
My VW SDI gets oil and filter every 5k. Semi-synth, better than VAG's minumum grade. Cost? 30ukp + half hour. Value to me? Piece of mind (the car needs to last), and whats 30ukp when a new engine is 1k!

The moral of this story is: stick to manufacturers recomendations (viscosity, type, frequency) and you won't go far wrong. For extra piece of mind, better oil more frequently won't harm anything other than your wallet, unless you shove Mobil 1 in my old marina :-)

Joe
Oil (final answer?) - eMBe {P}
Re. why Mobil1 costs more - I thought I had given a reason : marketing hype. ( similar reasoning to why "brand X" paracetamol or ibuprofen costs more than the generic version.)

Re. allowing filters to "clog up": This is what John S said -
".... I must admit, for that reason, I don't bother with a filter change. In fact a filter is more efficient once it's been used for a while, and given the same filters are used on the current cars which can do 15k between services I simply don't worry. ..."

He also said:
"...Inevitably, unless cars are operated on an oil condition monitoring system like major industrial plant, then any oil change recommendation is based on 'average' usage. There's no doubt that the 6month/5000miles advice falls in to this category, and is based on the assumption that precautionary early changes are better than late changes. Does mineral oil need changing sooner than fully synth.? On the face of it, yes, except that engines which are designed for, or only need, basic oils (eg lower specific power outputs) don't stress the oil to the same extent as the engines which need the higher spec. oils. Therefore the oil lifetimes are perhaps not so different as the oil specs may imply. Then you get the people on this site who use the best, rather than the cheapest, oils for their cars which confuses this logic. Hence, no doubt, HJs broad brush recommendation. At least the service indicators such as those on the BMW use some sort of analogue to estimate oil lifetime. ..."

and
".... Modern American engines are not that different from their UK counterparts, although specific power outputs are often lower. The Americans have been using low viscosity oils for many years for efficiency purposes, and things like hydraulic lifters were common there before they were in the UK - the mechanical quietness of their big V8 is amazing. I believe you're right that the manufacturers are more conservative, but then their customers expect more from the product in terms of engine life. Equally, the owners are perhaps more aware of what the oil does, and the quick-lube shops which provide instant oil and filter changes with good quality products at low prices take the problems away. It's not just the USA that's more cautious. I believe that the up to 30k service interval for the new Vectra is UK only - other markets have shorter service intervals. This is allegedly demanded by the fleet operators who buy a huge proportion of new UK cars. They have little interest in the car past 80 or 100k miles, apparently unlike many users of this site.
Regards John S ."
Oil (final answer?) - J Bonington Jagworth
"30k service interval for the new Vectra is UK only - other markets have shorter service intervals. This is allegedly demanded by the fleet operators who..have little interest in the car past 80 or 100k miles"

Or to put it another way: 'Exploding the myth of 30,000 mile oil changes'!

Back to square one, I think...
Oil (final answer?) - THe Growler
>>>>I once had a Morris Marina .

Actually I thought they were not too bad a car. The "Ital" version in 1970's BL Excrement Brown cut quite a dash next to the coke bottle Mk III Cortinae and metallic blue Capris beloved of the DP dept, not to forget the bilious yellow Hillman Avengers of Credit Control. As for the metallic burgundy sported by the Acccounts Manager's Allegro, the less said the better. He used to arrive by taxi twice a week and swore blind his wife needed the car to pursue her charity work but we knew better, that it was in the garage being fixed yet again.

Amazing how the subject of engine oil brings out the latent anal retention in everyone. Either you can be swept up in the delirious adventure of modern automotive oil technology and never ever change your oil provided you check your filter is sufficiently clogged up to work properly, or you can risk your life once a quarter propping your car up on bricks and cancelling all appointments for the weekend because your oil has gone (according to the speedo reading) 23 miles beyond what the manufacturer says it should have.

If engines could talk I wonder what they'd say?






Oil (final answer?) - M.M
>>If engines could talk I wonder what they'd say?

Please change me every 6K??

M.M
Oil (final answer?) - tunacat
LOL, Growler!

I wonder how many people on this forum have suffered untoward engine damage, irrefutably attributable to using not-quite-the-ideal oil grade, or changing it and/or the filter too frequently or infrequently?

I believe the Ford CVH had a reputation for being bad for Black Sludge, but was that because users were not following Ford's recommendation for grade or change intervals, or was it because of the phasing out of lead or sulphur in petrol, or a weakness in the design of its exhaust gas recirculation system?

Surely BackRoomers have enough nous to use the correct type of oil, check its level regularly, change it and the filter at reasonable intervals, not wring the engine's neck until it's warmed up, and let it idle a little before shutdown in the case of turbos. In which case I'd have thought the results of using brand X rather than brand Y of oil which is supposed to be for the same application would be very difficult to discern.

I've run cars ranging from Morris Minor, 2CV, Fiat 126, through Ford, Fiat, Citroen, Nissan, to Subaru Turbo. Privately, my dad's run Renault, Peugeot, BMW, Fiat, Toyota, Skoda. They've done short trips, long motorway hauls, A-road thrashings. Depending on the vehicle, we've used everything from £3 no-brand 20W-50 to Mobil 1. At various times on various cars Molyslip, Slick50, Activ8 and ExtralubeZX1 have been added, just for the heck of it.

As a private users we simply stuck to changing the oil every 6000 miles and the filter every 6 or 12000, but we didn't bother if we overran by 1000 or so. Neither of us has ever had an engine fail or apparently suffer undue damage or wear due to the type or condition of the oil. Even the Minor's engine went well and seemed fine at over 100,000 miles.

I can maybe see some benefit for fleet managers if their cars need an oil change only every 30,000 miles, but as a private user I'd always just buy something of the manufacturer's recommended grade, meeting or exceeding the recommended specification, and on a modern car change it every 6 - 9000. Even with Mobil1, the cost of an oil change is not very significant compared with the cost of the petrol you've put in in that period.
Oil (final answer?) - eMBe {P}
eMBe i cant believe you can reccomend someone to put that
£3 oil in a car.


All I can say on a public forum is "Ask Wilinson to tell you who their supplier is". You will find that the majority of its fluids are "re-badged" identical items from a well known quality supplier, and you would pay 3 times as much for the original label for the identical product!
Oil (final answer?) - Ben {P}
A friend of mine works for a very large motorfactor chain. Even at the prices they buy in at there is no decent oil available for £3 for 5 litres.

John s did not say leave it till the filter is cloged up. He said it is more efficeint once it has been used for while. He has not changed, as the filter is capable of 15k- ie he has changed the oil before this point.

How do you know what Mobil 1 actually costs. In the published data, Mobil 1 marginally outperforms other oils on the market. Maybe their additive packages cost a bit more to produce. All synthetics are not the same. But there is little difference amongst the leading brands. When i use full synth in a car i use valvolene because i can get it at a very reasonable price round the corner.

Without a computer, or regular anylsis of your oil, you have to make your own judgement re your oil- ie guess. The longer the oil change intervals the more chance of engine problems. It all depends how long you want your car to last.

If i am keeping a car, i use synthetic where i can, becuase i cant be bothered to keep changing the oil!

What i want to know is can a low viscosity oil (ie 5W-30) in the correct situation, provide as much protection as a higher viscosity oil (15W-50)?
Oil (final answer?) - J Bonington Jagworth
" the filter is capable of 15k"

Er, how do we know this? Surely it's the same problem as for the oil - it depends on a load of variables that are difficult to assess, so the safest response is to change both regularly.

I'm still not convinced that a partially clogged filter will work better than a new one. It might catch a few finer particles when the escape channels are getting smaller, but by then the bypass valve will be sending the bigger ones straight back into the engine!
Oil (final answer?) - THe Growler
If a filter becomes efficient when older than when new it would be fitted with finer filtering faculties in ther fffffirst place.
Oil (final answer?) - Sooty Tailpipes
I have seen some cheap oil in Homebase say "for use where a 20W/50 oil is recommended"

So is it SAE20W/50 (not that I want it anyway) or is it a con?
Oil (final answer?) - Ben {P}
Does it say SAE on the container?
Oil (final answer?) - Blue {P}
What engines available in the uk actually recommend 20W50?

I mean if I put that in my car it would pack up and die in no time!

Blue

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