Crude based or synthetic oil ...

cameo wrote in news:jimitt$n2p$ snipped-for-privacy@dont-email.me:

How many miles on the Accord?

How many miles per year?

What part of the country do you live in?

What kind of driving do you do? Lots of city, lots of highway? An even mix?

cT 0.99

both engine management systems and engine oils have moved on since the

1950's when the 3000 mile change was recommended. you need to too. use ordinary oil and go ahead and change it per the owners manual. if you want to use synthetic, you can exetend that period considerably.

if you don't believe, pay for oil analysis and get the hard facts for yourself. [it's cheaper than paying for constant oil changes like you're doing now!]

oh, and most "synthetic" oil these days is mineral based. a little more refined maybe [they call it isomerization], but mineral based nevertheless. don't get suckered into the hype unless you know what you're doing. or paying for.

irrelevant.

hardly relevant unless it's really low.

unless it's alaska or nevada, that's hardly relevant either.

at 3750, that's irrelevant too.

try to look at the big picture - the guy's almost certainly a troll given that this topic has been beaten to death countless times before.

and you're not helping with your inconsistency between your recommendation to stick to the owners manual on any topic EXCEPT oil change intervals, where you go completely nutso and would have people superstitiously changing their oil every day if you could.

300,004 miles.

Now that I retired, only about 12,000.

Puget Sound.

About half suburban, half freeway.

cameo wrote in news:jiogc7$eg9$ snipped-for-privacy@dont-email.me:

You surely fall under the "Regular" maintenance interval, which calls for an oil change every 6,000 miles or 12-months. The "Severe" interval calls for 3,000 miles or 6-months.

Personally, I'm not comfortable leaving oil in for a year on an engine with as many miles as yours. Have you considered changing your oil twice per year? That would give you a 6,000 mile / 6-month change interval, which seems reasonable to me.

However, you may also want to consider the possible beneficial effects of your previous frequent changes. Your attainment of 300K is likely partially due to those frequent changes. Older engines produce more blowby and load- up the oil with deposits more than newer engines. It is wise to /increase/ the frequency of oil changes with age. My Integra has just over 380,000 miles on it. I change my oil at about 3,500-4,000 miles.

In short, summarizing the other posts - I guess you can skip the midway oil change ANYWAY, and certainly if you switch to synthetic, which would still see a change every seven months or so.

But, are you burning any oil with the old engine? If so then you will have to remember to check it and maybe top it off, and what's more you may actually be polluting the oil faster than a younger car would and this might make your current plan the best.

J.

I can't get excited about synthetic...

With modern oils, the big issue is contamination. (The oil itself is still a wonderful lubricant come the end of a change cycle.)

Synthetics get contaminated just like any other oil.

If you care about the car, plan to keep it a long time and/or make a lot of short trips, change more often!

If not, take the change intervals out.

There are way to many variables to cover in a post here... but I'd stay with the mineral and save the money. Keep in mind that oil is cheaper than metal any day.

Erik

PS, Look at your manual again and see if it says something about severe, dusty conditions or some similar wordage... it probably does. Those recommendations more 'real world'.

Erik wrote in news: snipped-for-privacy@news.dslextreme.com:

I do.

After about 180,000 miles with Mobil 1, I find it absolutely astounding that the head is still shiny-silver inside. No varnish. At all. Synthetics seem to produce far less varnish than mineral oils, and to be much better than mineral oils at keeping contaminants in suspension.

My head gasket failed after the first 200K, which were passed with Castrol GTX and an oil-change interval of not more than 3,000 miles. When I got the car back, the head had been totally cleaned of all the brown varnish which had previously been there. At that point I switched to Mobil 1, and have not looked back. I've owned the car since new, so I know exactly what's been done to it over the years.

I forgot to to answer the OP's question regarding synthetic oils. And my answer is, "The stuff is awesome! Use it, for sure!".

on what exactly do you base this "discomfort" and "intuition" tegger?

a. is it oil analysis? [no.] b. is it the owner's manual? [no.] c. is it superstition? [rhetorical.]

frankly, without any basis in fact, you're simply polluting this group with ignorance.

only if you [incorrectly] presume the manufacturer hadn't already thunk of that when they did their homework. homework you've never done because you've never done oil analysis.

particularly with synthetic oil, that change interval is not just ignorant, it's absolutely insane.

go get some oil analysis tegger - just like the professionals who manage machines with billions of dollars and lives at stake. go get some facts.

I do burn about a quart of oil between current oil changes at 3,750 mile intervals. So I replenish that much during that time span.

By the way, I happened to talk to a mechanic about this issue after I posted my message and he said that even if the synthetic oil could allow me to skip that "mid-term" oil change, one oil filter could be a problem for 7,500 miles. Hm, it never even occured to me and so far none of you mentioned itt either. It sounds reasonable though, but what do I know?

Actually for my car "regular" is every 7,500 miles and "severe" (what I adhere to) is half of that, 3,750 miles.

You didn't read my post very closely. I've been changing at every 3,750 miles and that happens more than twice a year.

Pretty much what I am doing.

???????????? what kind of "mechanic" is this?

the reason nobody mentioned it is because it's not an issue. when you have cars with 10k or even 20k mile oil change intervals, filter clogging is rarely an issue. a honda with a modern multi-million dollar maintenance minder wouldn't tell you to change the filter more frequently than the oil, and honda's conservative oil management will typically last 7-10k miles. how could any special departure from that just for the filter seem "reasonable"?

Maybe the kind who knows the whole engine is pretty loosey-goosey burning a quart every 3,750 miles? Reminds me of my old Alfa, where you had to dump the oil into the gas tank every fillup. Ah, the old days!

Cuz he's in a much older model?

I'll leave it to you experts to judge whether and how you want to use synthetic oil in a car burning it at that rate, my guess is - you don't.

J.

that doesn't burn filters though dude. if anything, the fresh oil being added keeps it healthier - things like the drain-back valve don't become so inflexible and the fresh detergents keep the fine particles from precipitating.

doesn't matter. the 94 has a very good engine management system - it certainly doesn't load a filter in only 3.75k miles. not even 7.5k miles.

since most car "synthetics" are in fact just "group III" mineral oils, and most "ordinary" oils are now "semi-synthetic", most of the differential advantages are substantially eroded and really just down to the additive package.

but those additives can be markedly different. some oils without good seal conditioners [motorcraft brand] will let shrink seals like crazy. others like castrol gtx have good seal conditioners, but as tegger relates regarding deposits, is less good for detergents. bottom line, good branded "synthetics" are indeed good oils with great additive packages. and if synthetics are used, it's completely pointless sticking to the traditional oil change intervals.

as for oil burning, i wouldn't hesitate to use a synthetic in a burner. my experience is that with the good detergent package actually cleaning the engine, the rings tend to free up and consumption can drop significantly. my 89's engine was burning at the rate of a quart per thousand when i first got it with 105k on the clock. after about 2 years of synthetics, the engine had cleaned to the point you see in that flickr pic, and today, the oil consumption rate has dropped to about half a quart per 5k miles.

Yeah, well some of us find that varnished finish on the engine's innards attractive. Reminds me of how nice the wooden hull, mast, and boom looked on my old 1950's vintage sailboat after I refinished them each year.

Hell, next thing you know, I may have a sign painter put a name and home port across the trunk of my Accord...

cameo wrote in news:jipgg1$u3f$ snipped-for-privacy@dont-email.me:

I read it very closely indeed, thank you.

My "not comfortable" statement referred to the 1-year interval for "Regular" service in the manual I have. I guess I should have put those two paragraphs together so it was more clear that they were directly related.

My proposal for you was to change from replacing your oil 3.2 times per year to 2 times per year. This would still be in keeping with the factory's recommendations for "Regular" service..

that's an encouraging departure from "You can never change your oil too often".

you need to get some facts under your belt on this topic tegger. you're happy to stick to the book on most things, but on oil changes, your mind is completely warped. spend the money on oil analysis like professional [aerospace, marine, military, railroad, haulage] engineers and fleet managers do. and learn not to let superstition rule your life.

SMS wrote in news:4f50f8fa$0$11964 $ snipped-for-privacy@news.sonic.net:

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Not true at all. You can switch back-and-forth anytime you like between mineral and synthetic.

not true. in the old days of ester-based synthetics, that was more of an issue, but these days, most "synthetics" are just refined mineral oils so there is no shrinkage to start with, and on top of that, they add seal conditioners. at this point, it's just an old wives tale.

if you read the wording more carefully, you'll see the difference between the headline and the legal c.y.a. but the reality is most synthetics can extend change intervals substantially.

see above.

contamination is what the filter is for. unless you have a low grade filter that starts to internally leak, contamination isn't an issue because particle size is kept below the oil film thickness size - and by some margin too.

indeed.

if you're sticking to factory change intervals. and are using a decent quality standard oil. [most standards are semi-synthetic now anyway.] but if you use extended intervals, which you can, synthetics are a substantial improvement.