Under near ideal conditions with almost all highway driving at reasonable speeds, no cold temps, etc., what do you all think is the max OCI for a name brand conventional (PYB, etc) with a quality filter is?
Max interval for conventionals
- Thread starter gfh77665
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It depends on the condition of the engine and what engine. You would have to test and find out for yourself.
Well dnewton is running 15000 mile intervals on supertech and a nothing special filter under less than ideal conditions and his used oil analysis come back that the oil has life left,so taking that into consideration under ideal conditions 20000 miles.
For most engines the max OCI for dino oil is about 7-10k under ideal conditions, if the engine is in good working condition and fairly lean to begin with.
My 1994 LS400 had/has 7-8k/6mo OCI with dino since new, back then the oil was SG or SH the newest SM/SN is much better than 20 years ago. The engine has no fluid(engine oil or ATF or PSF) related problem with more than 360k miles on odometer until few months ago, when it started to have oil leak from the original valve cover gaskets. I think valve cover gasket lasted 350+k miles is very good.
My 1994 LS400 had/has 7-8k/6mo OCI with dino since new, back then the oil was SG or SH the newest SM/SN is much better than 20 years ago. The engine has no fluid(engine oil or ATF or PSF) related problem with more than 360k miles on odometer until few months ago, when it started to have oil leak from the original valve cover gaskets. I think valve cover gasket lasted 350+k miles is very good.
Originally Posted By: dave1251
It depends on the condition of the engine and what engine. You would have to test and find out for yourself.
"Under near ideal conditions..."
It depends on the condition of the engine and what engine. You would have to test and find out for yourself.
"Under near ideal conditions..."
Again what engine.
There was a link a few years ago posted about a guy who did medical deliveries in a Scion xB with the 1.5; He had something like 425,000 miles on it, all done with 20-30K OCI on dino oil.
What about sump size ? A 4.25 qrt. Hyundai OR a 7.0 qrt Chevy Trailblazer ? For a compact with a small 4 qrt sump : 5,000 miles . For the larger 7 qrt. sump 7,000 to 10,000 miles ... I would push a synthetic harder than a dino though (unless you like a greater risk of sludge) .
3000 miles. Any further than that, you're looking at varnish. I change mine at 2000 miles.
Originally Posted By: dave1251
Again what engine.
The question was posed in a generalized sense. I thought that was very easy to see. It is not specific to any particular engine.
Before you take exception with the generalizations, note that the majority of owners manuals from many brands typically suggest 7500 miles OR 3750 severe.
Thanks to all who gave constructive answers and opinions without getting needlessly bogged down in semantics.
Again what engine.
The question was posed in a generalized sense. I thought that was very easy to see. It is not specific to any particular engine.
Before you take exception with the generalizations, note that the majority of owners manuals from many brands typically suggest 7500 miles OR 3750 severe.
Thanks to all who gave constructive answers and opinions without getting needlessly bogged down in semantics.
At almost all highway miles? My 93 ciera owners manual says 7500, and that was when SG oil was in service. Should be no problem for an SN oil
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Originally Posted By: gfh77665
Originally Posted By: dave1251
Again what engine.
The question was posed in a generalized sense. I thought that was very easy to see. It is not specific to any particular engine.
Before you take exception with the generalizations, note that the majority of owners manuals from many brands typically suggest 7500 miles OR 3750 severe.
Thanks to all who gave constructive answers and opinions without getting needlessly bogged down in semantics.
Then why ask the question?
Originally Posted By: dave1251
Again what engine.
The question was posed in a generalized sense. I thought that was very easy to see. It is not specific to any particular engine.
Before you take exception with the generalizations, note that the majority of owners manuals from many brands typically suggest 7500 miles OR 3750 severe.
Thanks to all who gave constructive answers and opinions without getting needlessly bogged down in semantics.
Then why ask the question?
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Originally Posted By: dlundblad
Originally Posted By: Merkava_4
3000 miles. Any further than that, you're looking at varnish. I change mine at 2000 miles.
2000 miles? I too like to live dangerously.
merkava is kidding I hope
Originally Posted By: Merkava_4
3000 miles. Any further than that, you're looking at varnish. I change mine at 2000 miles.
2000 miles? I too like to live dangerously.
merkava is kidding I hope
If you're driving highway miles and your engine isn't receiving coolant or fuel from other parts of your vehicle, today's conventionals could easily go 7,000 miles. Again, you're risking it beyond that in case any problems should occur that you are unsuspecting of. I usually change my Dino's at 4k and my syns at 7k.i like to play it safe.
Originally Posted By: ChevyBadger
merkava is kidding I hope
Not entirely kidding. My OCI is 6 months and it just so happens that I log in 2000 miles every 6 months. But if I was driving the car further each day and somebody could guaranty me that I would have no varnish at 5000 miles, I'd do it.
merkava is kidding I hope
Not entirely kidding. My OCI is 6 months and it just so happens that I log in 2000 miles every 6 months. But if I was driving the car further each day and somebody could guaranty me that I would have no varnish at 5000 miles, I'd do it.
Originally Posted By: Merkava_4
3000 miles. Any further than that, you're looking at varnish. I change mine at 2000 miles.
Absolutely absurd. The oil in my car would be just darkening enough to see it on the dipstick at 2000 miles.
I suggest reading and absorbing what bitog has to offer. You aren't a trailblazer being the sole member who believes such absurdities however if your interested in being credible you might want to reconsider your position
3000 miles. Any further than that, you're looking at varnish. I change mine at 2000 miles.
Absolutely absurd. The oil in my car would be just darkening enough to see it on the dipstick at 2000 miles.
I suggest reading and absorbing what bitog has to offer. You aren't a trailblazer being the sole member who believes such absurdities however if your interested in being credible you might want to reconsider your position
Originally Posted By: Clevy
Absolutely absurd. The oil in my car would be just darkening enough to see it on the dipstick at 2000 miles.
I suggest reading and absorbing what bitog has to offer. You aren't a trailblazer being the sole member who believes such absurdities however if your interested in being credible you might want to reconsider your position
OK then -- what's the maximum mileage you can run a conventional oil without developing varnish ?
Absolutely absurd. The oil in my car would be just darkening enough to see it on the dipstick at 2000 miles.
I suggest reading and absorbing what bitog has to offer. You aren't a trailblazer being the sole member who believes such absurdities however if your interested in being credible you might want to reconsider your position
OK then -- what's the maximum mileage you can run a conventional oil without developing varnish ?
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