Benefits of Running a Larger Oil Filter? (Cold starts etc)
- Thread starter jtay2024
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Zee, I don't disagree with you. Cleaner oil definitely cause less wear. And by the way, I use better filter nowadays just because I am a geek and spend too much time on bitog. But based on my experience the difference is minimal.My viewpoint is that it takes a better efficiency oil filter to achieve cleaner oil. Cleaner oil will always result in less wear with all other factors held constant, especially the longer the OCI, where a higher filter efficiency would benefit the most. Based on lots of studies, there certainly could be a wear level difference over the long run due to filtering efficiency - I'm talking a 99% @ 20u vs a 50% @ 20u or a 99% @40+ micron filter. It's not going to make a noticeable difference over an OCI or two ... it's over the long haul of the vehicle. Graph below shows the difference between 99% @ 20u, 30u and 40u filtration.
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The bottom line is that the oil filter is the last thing to take care of any debris that enters the oil, regardless if that debris in generated internally inside the engine or is ingested from outside the engine, like from a bad or inefficient air filter. It's just funny that some people seem to believe that filtering oil better than not doesn't make any difference ... guess that's because their engine doesn't "blow-up" when using a low efficiency filter, which seems to be a common metric for if something works "good" or not in an engine.
I used to own a 1991 Honda Accord and all its life I used the cheapest oil and oil filters there were. I don't remember what KMart used to sell back in the day, but that is what I used. Then Walmart came along selling I believe were STP filters and I used those. Then Walmart started selling Tech2000 filters and oil and I used those. Then went on to Supertech filters and oil. I'm pretty sure I used a few fram orange cans here and there. To make it worse, the oil filter was on the back of the engine and I hated changing it, so I was only changing the filter every other time. So for almost all its life this car had 3k mile oil changes and 6k miles filter changes with the cheapest oil and filters available. I scrapped the car at around 375k miles, not because of engine issues, but because the body fell apart. In this case super duper oil and filters would have not made any practical difference.
I wish I would have known about cutting oil filters open back then to see how those cheap tech2000 filters looked after 6k miles.
I’m going into the larger oil filter business let me know your make and model, so I can provide a longer dip stick and a slap on sticker that says warning larger oil filter increased oil capacity.
Yeah, theirs is no real point or benefit to using an oversize filter in the first place.
Yeah, nobody has a real time particle counter on their engine, so it doesn't hurt anything to use an efficient oil filter to ensure the oil is keep cleaner than not regardless of the OCI. As mentioned many times in these discussions, the longer the OCI, the more important a higher efficiency oil filter becomes.
Re: Your bold statement ... 3000 mile OCIs wouldn't benefit much from a real high efficiency filter as mentioned before, but I'd still want to use one that was 95% @ 20u or better ... "just because" you never know what might get into the sump. If anything gets by the air filter and into the sump, then the only other filter left to catch that debris would be the oil filter. Even the Fram orange can is that efficiency, and hard to say what some of those other old brand filters you used had for efficiency.
There are only two ways to keep the sump from becoming overly dirty: 1) Filter it better, or 2) Perform an oil change. If someone doesn't want to do 3K-5K OCIs, then run a better efficiency oil filter for longer OCIs.
Wait, so I won't hurt anything by going to a bigger filter with a 10psi bypass from a slightly smaller filter with a 15psi bypass?
Doubt a larger filter, unless it was 2 or 3 times the media area, would decrease the dP by 5 PSI under the same operating conditions.
If you look at typical dP-flow curves for an oil filter, they are pretty non-linear at high flow rates. For the dP to drop by a third, there would typically only need to be around 25% more media area. When the oil is thick and flow rates are low, the flow would be more laminar and the dP-flow would be more linear. In this case around 50% more media area would be required.
It would be better to use a larger filter with the same 15 psi bypass setting if one is available, for an even lower chance of bypassing with no real downside.
Zee, my other example is my former 2004 Sprinter work van. I bought it new and I put almost 800k miles on that thing before retiring it. Original engine and transmission, never been opened up. Only replaced one injector, an EGR valve and a couple water pumps. Ran as good as new when I gave it to a neighbor about a year ago. In the beginning I was doing 10k oil and filter changes, then I did some oil analyses and extended it to 15k. Oil was still serviceable at 15k miles, additives were still plentiful and wear metals were still better than average according to Blackstone, but kept oil and filter changes at 15k. I used a mix of Mann, Mahle and Hengst filters which are not known for their super efficiency. Somehow these filters were able to keep the oil clean enough to get to almost 800k miles with extended oil changes.
Like I said before, now if I have a choice I will use a more efficient filter, but does it really matter that much?
Every vehicle is different, and used and maintained differently. But the simple thing to do is use a pretty efficient oil filter (IMO, 95% @20u or better) because nobody knows exactly what's happening inside the engine and the level of cleanliness of the sump every minute over the length of the OCI. It's cheap insurance to ensure the oil is filtered better than not. The oil filter is the only thing left to remove particulate once it has gotten into the oil. It just makes me chuckle when people on this site believe they know what's going on inside their engine every minute it's in operation, and somehow conclude that less filtration is the best thing to do. UOAs only show a very small sliver of the wear metals particulate size (5u and smaller), so it's really pretty insensitive to any abnormal wear going on unless you have a long history of UOAs under the same basic use conditions. Knowing what you know these days, would you use a filter rated at 50% @ 20u or 99% @ 45u if you could get much better filtering efficiency for a few buck more?
Maybe with a "disposable" vehicle that they don't care about what oil or filter they use, some people would opt for anything regardless of the product performance. But most here believe that cleaner oil is better than not, and most will use oil filters that are rated better in efficiency than not, some regardless of the OCIs they use just for the insurance that the oil if filtered well. A few more bucks for added filtration isn't a bank breaker for most. Just forgo one Big Mac once every 6 months and spend it on a better filter is my viewpoint.
If I could run a filter 2X sized of factory sized oil filter I would….. and that goes for ANY vehicle.
Just hit 60K miles on OG Fram Ultra 7317 on Mazda CX-5. Will try for 80K miles but they might move and I will have to cut this extended oil filter experiment short.
2.5L non turbo engine holds 5 quarts with drain & refill.
Just hit 60K miles on OG Fram Ultra 7317 on Mazda CX-5. Will try for 80K miles but they might move and I will have to cut this extended oil filter experiment short.
2.5L non turbo engine holds 5 quarts with drain & refill.
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I would definitely pick a more efficient filter.
I know this is deviating a little from the subject here, but I'm going to ask anyway. If you have a choice between 95% at 20 microns and 99% at 30 microns, which would you pick?
Too close to know ... I'd have to see the entire efficiency vs particle size curve. They may be very close to each other. Example, look at the ACDelco in the Ascent testing data graph below. The ACDelco is 96.5% @ 20u and also 99.3% @ 30u. That's a close example to your question.
In this case, either one would be basically equal in filtering performance over the particle size spectrum. It would be nice to be able to compare all filters at 20u ... it should be a standard made in the oil filter industry IMO, and be reported that way by all makers who have an ISO 4548-12 efficiency claim. But they like to play advertising games by using the particle size at 99% because "99% efficiency" sounds better than "95% efficiency" or "50% efficiency". Most people don't even know what a micron is, so hey, go for the one that's "99%", lol.
Yes, after looking into the relationship deeper, looks like an approx 40% change in flow area would reduce the dP by approx 50%. Doubling the flow area (100% increase) would reduce the dP to approx 25%. This correlated close to your 25% increase in flow area gives 1/3 drop in dP. My WAG was off without running numbers. It's relatively time consuming to see the actual relationship with calculated numbers as I did below.
I used that dP calculator you've referenced before (setup to for a square perforated plate tweaked to give the curve below), and in all cases the flow was actually shown as laminar and the graph was not linear at all. Basically comes out to Y=X^-2 with all other variables held constant. X = Flow Area, Y = dP. The graph below was created with the viscosity and flow rate held constant, and only the flow area was changed.
When the flow rate through an oil filter is low, which is most of the time unless the car is on a race track, the dP with hot oil is pretty low to start with. So increasing the media area by ~40% would only reduce the already low dP by 50%. Yes, in an engine where the max flow rate is super crazy, like in those Subarus, and if the oil if relatively viscous, going over-sized filter with 40-50% more media area could make a noticeable difference in the max dP seen across the filter.
Here's the above graph plotted on Log-Log scales. X-axis is Flow Area, and Y-axis is dP.
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I played around with data above pertaining to the change in dP as a function of the media flow area, with all other factors constant.
Applied it to the PureOne PL14006 "Flow vs Delta-P" data I had from Purolator's actual lab flow bench test, and that curve is the baseline Flow vs dP curve ("+0% Area"). This is with hot oil at 11.5 cSt, and for instance gives ~4.1 PSI dP at 10 GPM. If the media area was increased by +50%, the dP at 10 GPM would be ~1.9 PSI. If the media area as decreased by -50%, the dP woud be ~6.4 PSI. Could also apply the viscosity change factor on top of this if you want to see the effect of both media area and viscosity on the Flow vs dP curve.
Applied it to the PureOne PL14006 "Flow vs Delta-P" data I had from Purolator's actual lab flow bench test, and that curve is the baseline Flow vs dP curve ("+0% Area"). This is with hot oil at 11.5 cSt, and for instance gives ~4.1 PSI dP at 10 GPM. If the media area was increased by +50%, the dP at 10 GPM would be ~1.9 PSI. If the media area as decreased by -50%, the dP woud be ~6.4 PSI. Could also apply the viscosity change factor on top of this if you want to see the effect of both media area and viscosity on the Flow vs dP curve.
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(3) increase sump capacity.
Sure, but who's going to change out the oil pan for a larger one unless you're a big time racer. Yes, some high performance engines come with a higher sump capacity, like 8 to 10 quarts instead of 5 or 6 quarts.
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Yes but that's a whole other story. The little 4967 vs 3600 gives 2 whole inches in height and maybe 1/4 " in OD. I'm thinking this would help a 3.9 qt. capacity sump a bit especially a longer drain.
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