If you run 95% highway, you should be able to run a 10,000 mile OCI on most synthetic oils. Granted, it has to be a good synth but the 10K should be good correct or not?
TIA
TIA
Why are most synthetic OCIs at 6k miles or less?
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If you run 95% highway, you should be able to run a 10,000 mile OCI on most synthetic oils. Granted, it has to be a good synth but the 10K should be good correct or not?
TIA
Nope.
IMO, you should get a UOA with TBN to see how YOUR engine with YOUR driving style in YOUR area does.
I just got done with running Castrol GTX almost 6k miles with a TBN of 4.4 (blackstone which is lower than everyone else).
Others have run a "good" syn 5k miles and their TBN was 1.5 (again blackstone) so to each their own.
It matters HOW long you run ANY oil in YOUR conditions.
Alot here think because they are spending $$ for a name brand syn that they are covered and never worry about UOAs, TBN, OCis or such.
All they are doing is wasting $$.
Facts are a wonderful thing!
Take care, Bill
For those of you who claim to sample as opposed to completely changing your oil, what device or method are you using to accomplish that?
I agree with UnDummy that it's cheaper to change the oil than to hire a lawyer, hence the 5k mile OCIs in my '05 Toyota with PP 5w30. Once the warranty is gone, I think I'll try Amsoil and a once per year OCI, as the mileage is 9,500k or less per year.
And yeah, Bill in Utah, you can't just fill and forget based on brand name.
What other oil analysis companies are being used besides Blackstone? I've had consistent service from Blackstone, but all of my TBNs look weak after 5k with 50-50 highway-city and no fuel dilution. That includes green GC and PP.
I agree with UnDummy that it's cheaper to change the oil than to hire a lawyer, hence the 5k mile OCIs in my '05 Toyota with PP 5w30. Once the warranty is gone, I think I'll try Amsoil and a once per year OCI, as the mileage is 9,500k or less per year.
And yeah, Bill in Utah, you can't just fill and forget based on brand name.
What other oil analysis companies are being used besides Blackstone? I've had consistent service from Blackstone, but all of my TBNs look weak after 5k with 50-50 highway-city and no fuel dilution. That includes green GC and PP.
6000-8000 is what I recommend. Less or more are both silly, with the exception of short trips or low miles over a long time....or both.
Look at Mobil's Clean line, 5000-7500 miles is very reasonable. Doing something in that range with an otc synthetic is totally reasonable.
We keep our vehicles longer than you do and our OCI's with dino are much longer. Something ain't right?
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I'm sorta with undummy.
Most of those that your seeing are often evenly distributed time-wise. The mileage is incidental. Many don't like cycles that carry over into another year. That is, they don't want to do 9 month OCIs. So, it's 3, 4, or 6 months ..if they cannot rationalize one year.
I used to ask the "time in service" ..but sorta gave up when it was apparent that it fell into this sort of pattern more often than not.
I'm that way too. Spring and Fall ..unless I've got a specific mileage test going on.
There's an oil for almost ANYONE to do a 6 month OCI somewhere in the non-boutique market. Very ......VERY few fall out of that capability.
Most of those that your seeing are often evenly distributed time-wise. The mileage is incidental. Many don't like cycles that carry over into another year. That is, they don't want to do 9 month OCIs. So, it's 3, 4, or 6 months ..if they cannot rationalize one year.
I used to ask the "time in service" ..but sorta gave up when it was apparent that it fell into this sort of pattern more often than not.
I'm that way too. Spring and Fall ..unless I've got a specific mileage test going on.
Don't chase the TBN numbers between differnt oils, nor different labs. A "lower" TBN for one brand of oil may mean nothing compared to the same TBN for some other oil. What matters if the TBN is high enough. I've seen TBN's drop precipitously, then hold at a "high enough" level for a much longer time than you would expect, if you'd have drawn the nearly straight descending line plotting the early TBN drop.
I drove 30k last year, so 4 month changes were not looking so great. Why bother to conserve when I've already got whole room full of oil? So, it looks like 3 month intervals for me. That comes out to at least 8000 miles. The fact people use synthetic is not just for long ocis, some like the way their engines run, some need it for turbos and some need it for cold conditions. fwiw, I'm doing 4 months on my woman's CRV, that's about 6000 miles, not with synth though, Clean 7500.
I use a vac sampling pump. They are available from AMSOIL as well as several other vendors. Most sample bottles (Blackstone's and OAI's off the top of my head) screw directly to the bottom of the pump.
AMSOIL's OAI does quality UOAs. I use Blackstone over them simply because of their affiliation with AMSOIL. I sell AMSOIL products and as a result, when I do UOAs for customers, I want it to be crystal clear that the results are independant. I also prefer to pay when I sent in my sample instead of when I get the sample bottles. I have close to 20 Blackstone sample bottles on my shelf, I would rather not have that as a pre-paid investment.
While I agree with the first part of your statement, I completely disagree with the lab statement. If that were the case, why bother to sample and analyze? Just get a dart boad and see what result you get.
If equal analytical methods are used, the results should be statistically similar within the variability of the samples analyzed. If different laboratories provide a wide range of results, the first question I'd ask is why?; is it due to sampling technique, sample heterogeneity, analytical method(s), or is it due to poor QA/QC?
The typical UOA is probably ok for general use, but the typical UOA also doesn't seem to be good at detecting some common problems like sludging and such, so I would n't be betting the farm vehicle on UOA.
If you do use UOA then at least consider NOT averaging over multiple samples to get something like Fe/mi, as averaging is really designed to desensitize a measure to smaller amounts of variation, variation that you're probably wanting to see. Consider the 'neptune M1 study', where thye did a great job by sampling at 1k intervals on one study. If you disregard theire averaging and look at the incremental amount of Fe produced at each sample interval, it suggests to change you oil at 3k to 4k miles, or 7k to 8k miles at the most.
http://neptune.spacebears.com/cars/stories/mobil1.html
k miles raw adj fe/kmi incrmental Fe
1 10 10.0 10.0 10.0
2 12 12.0 6.0 2.0
3 14 15.2 5.1 3.2
4 19 22.2 5.5 7.0
5 23 28.8 5.8 6.6
6 26 34.7 5.8 5.9
7 27 36.0 5.1 1.3
8 35 49.6 6.2 13.6
9 38 57.0 6.3 7.4
10 36 54.0 5.4 -3.0
If you do use UOA then at least consider NOT averaging over multiple samples to get something like Fe/mi, as averaging is really designed to desensitize a measure to smaller amounts of variation, variation that you're probably wanting to see. Consider the 'neptune M1 study', where thye did a great job by sampling at 1k intervals on one study. If you disregard theire averaging and look at the incremental amount of Fe produced at each sample interval, it suggests to change you oil at 3k to 4k miles, or 7k to 8k miles at the most.
http://neptune.spacebears.com/cars/stories/mobil1.html
k miles raw adj fe/kmi incrmental Fe
1 10 10.0 10.0 10.0
2 12 12.0 6.0 2.0
3 14 15.2 5.1 3.2
4 19 22.2 5.5 7.0
5 23 28.8 5.8 6.6
6 26 34.7 5.8 5.9
7 27 36.0 5.1 1.3
8 35 49.6 6.2 13.6
9 38 57.0 6.3 7.4
10 36 54.0 5.4 -3.0
IMO, it's because if you have a oil-related issue (unlikely) then the warranty is invalid if you go beyond the recommended OCI. Refer to the previous statement about oil changes being cheaper than lawyers.
For me, 5000 miles worth of dirt is still 5000 miles worth of dirt and I want to get it out.
I run synthetics, change every 5000, get occasional UOA's, and I lease a new truck every three years.
Nine months left on this one. The line forms to the left.
For me, 5000 miles worth of dirt is still 5000 miles worth of dirt and I want to get it out.
I run synthetics, change every 5000, get occasional UOA's, and I lease a new truck every three years.
Nine months left on this one. The line forms to the left.
While I realize oil color is no indication of condition, I have to assume my car's refusal to blacken the oil before even 5000 miles has to mean it's very easy on the oil. I do a few short trips, but those are tempered by the trips on the interstate in off-rush hour and long-haul trips between New England, No. Va. and Florida. in doing 2500-3000 miles/month this way, I just don't find a reason to change so often. Last OCI was over a corroded filter around 6K, and the oil was barely off brand-new in color. Seemed like an extreme waste of oil. But that's just my car and usage. If I was doing a lot of stop and go, idling and the rest of the severe-service driving styles, it would make sense to 3K it, but this car just doesn't muddy the oil yet.
So there's my question: If I'm not darkening the oil deep into an OCI, do I need to change it anyway (even at 7500)? Or is that throwing good oil after bad? Forget the warranty issues, I don't care about those anymore.
So there's my question: If I'm not darkening the oil deep into an OCI, do I need to change it anyway (even at 7500)? Or is that throwing good oil after bad? Forget the warranty issues, I don't care about those anymore.
Get a UOA - it's the only way to know for sure.
I change my synthetic oil at around 6K miles because I am anal about my truck. On top of that, the truck also makes a lot of very short trips, is driven by three different people with very different driving styles, is driven hard, and does a lot of stop and go driving. I do not have a UOA to verify that I am doing the right thing, but I plan on getting one done one of these days.
I think outside of the world of BITOG, a lot of synthetic oils probably get changed early because people do not really understand what is different about synthetic oils. They just know that the label on the bottle of oil says it will give them more HP and that it costs more, so it must be better.
I think outside of the world of BITOG, a lot of synthetic oils probably get changed early because people do not really understand what is different about synthetic oils. They just know that the label on the bottle of oil says it will give them more HP and that it costs more, so it must be better.
Short trips, stop and go driving, extreme temps, etc so I just change every 6 months (May and November). Even with the recent increase in PP and Motorcraft filters price it still only costs under $120/year ($30x4) for the car and van for oil changes. Big frakkin deal...
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