I change my PP every 6,000 miles-turbo I4 Mazda and did the same for Volvo, Subaru and Jeep 4.0. Cars sold running excellent at 127,000 to 158,000 miles. Friends vehicles have oil changed at 7-8,000 miles with Dino at a Pennzoil station and his cars sold at ~ 100,000+ miles running excellent. I guess my hobby is costing me dollars & time (DIM) but, keeps me out of psychologist offices? Ed
Long drain tranquility
- Thread starter ericthepig
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Originally Posted By: digitalSniperX1
Applying a bit of basic reasoning one might say "While wear metals per mile remain relatively constant, i.e. a linear function of mileage, then there are no ill effects to longer OCI's".
From what I've read this statement is basically true.
Well, I'd say that (mostly, anyway) the wear is what the wear is. Now one oil may not be ideal in producing low numbers by a tick or two ..even to a good percentage of increase ...some add packs can aggravate a given element, and surely some service variables may require some alteration in what oil you use (fine tuning)..
..but the main thing is how the oil holds up under the conditions it's subjected to. While lower numbers are always preferred, it's not the end all for an oil's suitability for continued use.
Applying a bit of basic reasoning one might say "While wear metals per mile remain relatively constant, i.e. a linear function of mileage, then there are no ill effects to longer OCI's".
From what I've read this statement is basically true.
Well, I'd say that (mostly, anyway) the wear is what the wear is. Now one oil may not be ideal in producing low numbers by a tick or two ..even to a good percentage of increase ...some add packs can aggravate a given element, and surely some service variables may require some alteration in what oil you use (fine tuning)..
..but the main thing is how the oil holds up under the conditions it's subjected to. While lower numbers are always preferred, it's not the end all for an oil's suitability for continued use.
Well, first let me say I'm not an expert. Also, even if a particular oil is rated for extended/long drain intervals, doesn't mean I'd go that far. In fact, I can say I'd never run an oil 35,000 miles in of any my vehicles unless they were constantly highway driven and had one of those nifty bypass filtering systems Amsoil sells. Even then I'd do it only with intermittent oil analysis. And they'd have to be out of warranty.
Having said that, over the life of a vehicle, if the wear metals per mile of driving found in accurate oil analysis (which is probably difficult to obtain) remain constant in both short and long drain periods, and are sufficiently low, then the negative effects of sludge buildup, if any, haven't been shown. I suspect if sludge was building up in sufficient amount then it would show itself as high wear metals in a UOA.
I can only surmise this on the theory that UOA's are a good wear indicator. I suspect they are since they are used by professionals and laymen alike to measure wear conditions in an engine.
If they are not, then all the above reasoning on extended drain intervals is suspect at best.
I can only assume that they would not be accurate if wear metals were somehow excluded from the used oil itself. I suspect this is possible if much of it accumulated on the drain plug magnets and/or if wear metals were somehow otherwise collected outside the engine oil.
Having said that, over the life of a vehicle, if the wear metals per mile of driving found in accurate oil analysis (which is probably difficult to obtain) remain constant in both short and long drain periods, and are sufficiently low, then the negative effects of sludge buildup, if any, haven't been shown. I suspect if sludge was building up in sufficient amount then it would show itself as high wear metals in a UOA.
I can only surmise this on the theory that UOA's are a good wear indicator. I suspect they are since they are used by professionals and laymen alike to measure wear conditions in an engine.
If they are not, then all the above reasoning on extended drain intervals is suspect at best.
I can only assume that they would not be accurate if wear metals were somehow excluded from the used oil itself. I suspect this is possible if much of it accumulated on the drain plug magnets and/or if wear metals were somehow otherwise collected outside the engine oil.
Agreed.
However, my statement was addressing the notion that higher wear metal content in an oil increases wear per mile. I suspect that might be the case. Having said that, if the wear metals per mile were constant in both short and long term drains, then it's probably a safe bet that the higher metal content in the oil ran for a longer duration isn't increasing wear.
However, my statement was addressing the notion that higher wear metal content in an oil increases wear per mile. I suspect that might be the case. Having said that, if the wear metals per mile were constant in both short and long term drains, then it's probably a safe bet that the higher metal content in the oil ran for a longer duration isn't increasing wear.
Now that I've made what some might consider a pitch in favor of extended drains, I just changed the oil in my wife's RDX which had just 3300 miles on it. It was Mobil 1 5w30. The car is driven 2-35 mile trips per week and the rest on very short, approx 3 miles each way 4-5 times per week+various other short trips. The maintenance minder is smart enough to register the short trips and was at 40% life remaining. I change it earlier because turbochargers scare me a little and therefore one might call me a chicken. I think it's also direct injected, although not advertised to be.
Now it's has Pennzoil Platinum in the crankcase along with one of those high dollar Amsoil filters. When its warranty expires (in several years), I'd love to use Amsoil's SSO in it.
I drive an RX-8 daily, almost exclusively 70 miles 4 days a week It's oil is changed using Amsoil XL religiously at < 3000 miles and it too gets one of those high dollar Amsoil filters. RX-8's are known to pollute engine oil with combustion byproducts and raw gasoline. I can see what appears to be soot in oil drained from it.
So now you know, I'm a chicken with these two vehicles at least one of which is known to be pretty hard on oil.
Now it's has Pennzoil Platinum in the crankcase along with one of those high dollar Amsoil filters. When its warranty expires (in several years), I'd love to use Amsoil's SSO in it.
I drive an RX-8 daily, almost exclusively 70 miles 4 days a week It's oil is changed using Amsoil XL religiously at < 3000 miles and it too gets one of those high dollar Amsoil filters. RX-8's are known to pollute engine oil with combustion byproducts and raw gasoline. I can see what appears to be soot in oil drained from it.
So now you know, I'm a chicken with these two vehicles at least one of which is known to be pretty hard on oil.
I change by time, not miles. 2-3-4 times a year. I personally like changing oil, so 3 months is great. Noting the mileage and OLM reading is merely a footnote. It's best to have nice fresh oil in for winter, and maybe change viscs too, (an opportunity for those who are reluctant to try 5w-20)? So Dec-Jan-Feb...you definately want to go over the winter w/o having to do the task in the cold.
I have a new car too, and would not hesitate to use dino for the 5000-6000 miles I accrue in that time...but I have a big stash of synth, so I just use that.
I have a new car too, and would not hesitate to use dino for the 5000-6000 miles I accrue in that time...but I have a big stash of synth, so I just use that.
Originally Posted By: digitalSniperX1
Well, first let me say I'm not an expert. Also, even if a particular oil is rated for extended/long drain intervals, doesn't mean I'd go that far. In fact, I can say I'd never run an oil 35,000 miles in of any my vehicles unless they were constantly highway driven and had one of those nifty bypass filtering systems Amsoil sells. Even then I'd do it only with intermittent oil analysis. And they'd have to be out of warranty.
Having said that, over the life of a vehicle, if the wear metals per mile of driving found in accurate oil analysis (which is probably difficult to obtain) remain constant in both short and long drain periods, and are sufficiently low, then the negative effects of sludge buildup, if any, haven't been shown. I suspect if sludge was building up in sufficient amount then it would show itself as high wear metals in a UOA.
I can only surmise this on the theory that UOA's are a good wear indicator. I suspect they are since they are used by professionals and laymen alike to measure wear conditions in an engine.
If they are not, then all the above reasoning on extended drain intervals is suspect at best.
I can only assume that they would not be accurate if wear metals were somehow excluded from the used oil itself. I suspect this is possible if much of it accumulated on the drain plug magnets and/or if wear metals were somehow otherwise collected outside the engine oil.
You bring up some good points, which spark more questions. UOA looks for a lot of things, wear metals being one of them. Iron seems to be a favorite, a magnet will collect iron, will that lower the iron that shows up in the oil sample?
Will a very good filter, like an Amsoil, Mobil 1, or a bi-pass filter system catch more garbage, trap it, and it not show up in the UOA because its been trapped?
My point is this, could the wear be occurring, but the numbers are lower because the filter system is so good its capturing more of the metals and they aren't showing up as much because they were filtered out of the oil? Yet the same wear exists?
A cheap filter could be showing high wear numbers various metals aren't being caught, but yet the same exact amount of wear exists, its just being caught with a better filter, and not showing up?
This would create a warm feeling and the same wear is there. The UOA will tell how much life the oil has left though, and that has its merits.
Thanks,
Frank D
PS I'm trying to learn more..........
Well, first let me say I'm not an expert. Also, even if a particular oil is rated for extended/long drain intervals, doesn't mean I'd go that far. In fact, I can say I'd never run an oil 35,000 miles in of any my vehicles unless they were constantly highway driven and had one of those nifty bypass filtering systems Amsoil sells. Even then I'd do it only with intermittent oil analysis. And they'd have to be out of warranty.
Having said that, over the life of a vehicle, if the wear metals per mile of driving found in accurate oil analysis (which is probably difficult to obtain) remain constant in both short and long drain periods, and are sufficiently low, then the negative effects of sludge buildup, if any, haven't been shown. I suspect if sludge was building up in sufficient amount then it would show itself as high wear metals in a UOA.
I can only surmise this on the theory that UOA's are a good wear indicator. I suspect they are since they are used by professionals and laymen alike to measure wear conditions in an engine.
If they are not, then all the above reasoning on extended drain intervals is suspect at best.
I can only assume that they would not be accurate if wear metals were somehow excluded from the used oil itself. I suspect this is possible if much of it accumulated on the drain plug magnets and/or if wear metals were somehow otherwise collected outside the engine oil.
You bring up some good points, which spark more questions. UOA looks for a lot of things, wear metals being one of them. Iron seems to be a favorite, a magnet will collect iron, will that lower the iron that shows up in the oil sample?
Will a very good filter, like an Amsoil, Mobil 1, or a bi-pass filter system catch more garbage, trap it, and it not show up in the UOA because its been trapped?
My point is this, could the wear be occurring, but the numbers are lower because the filter system is so good its capturing more of the metals and they aren't showing up as much because they were filtered out of the oil? Yet the same wear exists?
A cheap filter could be showing high wear numbers various metals aren't being caught, but yet the same exact amount of wear exists, its just being caught with a better filter, and not showing up?
This would create a warm feeling and the same wear is there. The UOA will tell how much life the oil has left though, and that has its merits.
Thanks,
Frank D
PS I'm trying to learn more..........
Last edited:
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Quote:
The UOA will tell how much life the oil has left though, and that has its merits.
While I've fought long and hard to assert that the metal readings are "wear" ..I think that the above statement is the one that has the most merit.
First you have to look at how the primary users of UOA use them. They don't fret wear metals. Sure, if something spikes or is radical ..the fleet owners is going to pay attention and take note ..he may consult the manufacturer and say "Hey, I just had 200ppm of Fe where 38 was the typical reading over the normal service interval ..they may fax the report to the manufacturer and see what they think about it ..etc...etc.
..but basically, for them, "the wear is what the wear is" ..it yams what it yams. They have one or two approved oils from all of the blenders ..and the service duty is what it is. It's that simple for them. They're looking for flaws or insults to the oil.
Now move to our realm and you've got services all over the place and virtually no high percentage of "steady state" operation that allows climate and whatnot to alter things around ..a broad span of target markets for the engines..varied power densities ..and all the other stuff that makes oil selection and service duty as individual as your preferred cusine and personal decor motif
So, in most cases, you're asking "Did the oil do its job?" (held visc, TBN, TAN/Oxi/Nit/etc within favorable limits ..and if there are any aggravating pests infesting the sump -airborne abrasives, fuel, coolant) .......THEN you look to see if the engine can be better served with another oil selection ..and if it makes a whole lot of difference if you do switch. As we can see with 4 identical samples, analyzed by 4 different labs, there's a testing variable. At least if you're trending, you're getting a typically consistent diffracted view.
Lower is always better ..and one would reason that there are all kinds of particles of various sizes that are routinely ejected from their resident bodies. Some will be in the detectable range ..and some will be larger. One would also reason, that above a certain size, that the larger particles that are above the detection level will also cause additional particle shedding over a few surfaces of various compositions. Some of these will get caught by the filter ..others will not
The UOA will tell how much life the oil has left though, and that has its merits.
While I've fought long and hard to assert that the metal readings are "wear" ..I think that the above statement is the one that has the most merit.
First you have to look at how the primary users of UOA use them. They don't fret wear metals. Sure, if something spikes or is radical ..the fleet owners is going to pay attention and take note ..he may consult the manufacturer and say "Hey, I just had 200ppm of Fe where 38 was the typical reading over the normal service interval ..they may fax the report to the manufacturer and see what they think about it ..etc...etc.
..but basically, for them, "the wear is what the wear is" ..it yams what it yams. They have one or two approved oils from all of the blenders ..and the service duty is what it is. It's that simple for them. They're looking for flaws or insults to the oil.
Now move to our realm and you've got services all over the place and virtually no high percentage of "steady state" operation that allows climate and whatnot to alter things around ..a broad span of target markets for the engines..varied power densities ..and all the other stuff that makes oil selection and service duty as individual as your preferred cusine and personal decor motif
So, in most cases, you're asking "Did the oil do its job?" (held visc, TBN, TAN/Oxi/Nit/etc within favorable limits ..and if there are any aggravating pests infesting the sump -airborne abrasives, fuel, coolant) .......THEN you look to see if the engine can be better served with another oil selection ..and if it makes a whole lot of difference if you do switch. As we can see with 4 identical samples, analyzed by 4 different labs, there's a testing variable. At least if you're trending, you're getting a typically consistent diffracted view.
Lower is always better ..and one would reason that there are all kinds of particles of various sizes that are routinely ejected from their resident bodies. Some will be in the detectable range ..and some will be larger. One would also reason, that above a certain size, that the larger particles that are above the detection level will also cause additional particle shedding over a few surfaces of various compositions. Some of these will get caught by the filter ..others will not
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