The definitive oil filter study

[Charlie_in_TX]

Karmak, the last thing I would call that 'study' would be definitive. 1st problem, it is not a scientific study. It does not use a scientific approach. 2nd problem, it does not ask much less answer the most important and basic question about a filter, HOW WELL DOES IT CLEAN THE OIL? A 'definitive' test would test, as a minimum, the filters effectiveness (how well it filters the harmful contaminants found in oil) and holding capacity (how much of the contaminant the filter can hold before it fails.

About 15 years ago Consumer Report ran the tests I discribed. The Fram oil filter filtered the oil the best.

Is Consumer Report the 'definitive' answer? No

Is a fella with a hacksaw the 'definitive' answer? No

 

[boustany]

Good point, but there is also the issue of 'best evidence'. A 15 year old Consumer's Reports study would be much more trustworthy than this more recent one if we knew filters hadn't changed since then. Unfortunately, we all know how some companies gladly sacrifice their reputation for quality (and often their customer's lives) for the sake of near term profits.

For example, I almost lost my entire family due to a known defect in a certain very popular minivan made by a US company. Turns out the coil spring are known to break, with catastrophic consequences to the tire, steering and braking systems. I repeat, this is a known defect. There is no recall in place (in Canada at least), just a 'fix on failure' order. When this happened to my wife, she was coming to a stop. It destroyed the left front tire, damaged the steering and braking. 5 minutes before she was travling at around 60 MPH. Imagine what could have happened. I will never buy another vehicle from that manufacturer again.

As consumers we have more than a right to know whats what, besides the lies we get through advertizing. Quite frankly, it never occured to me to cut open a filter, I took Fram's reputation for granted - just like assumed a car manufacturer wouldn't knowingly kill its customers post Pinto (hint, hint).

So I am very glad I read this study. It may not be scientific, but its the most complete piece of work on the subject I've ever seen. If there are others around, I would be delighted to read them. Unfortunately the author chose to compare the Ford 5.0L filter. I won't be needing any of those.

 

[Anonymous Poster]

I hardly think this is some guy with a hacksaw - looks to me that he went to a lot of effort to be as objective as possible and simply reported what he found. I'm not sure I would apply a 15 year report to current products, but perhaps the construction has not changed much since then.

One aspect of filtration that I personally infer is that I am very doubtful of a quality filtration media if the rest of the filter is poorly constructed. If the internal bypass is trying to seat against a piece of cardboard with a weak spring assembly, no way will it filter effectively at anything over 800-1000 rpm - the oil will bypass the media just as if you were running the engine at high rpms or if the filter were severly clogged. It may have the best filter media in the world, but if it's poorly held together what good is it?

I think almost any filter is able to carry a potload of gunk - if an engine is that dirty though, then I don't know that even a 2 qt filter will help. The internal passages will be sludged up. Most of us who debate this sort of thing are by nature more attentive to the mechanical stuff around us and are usually more conservative about maintenance anyway. For the guy who happily announces that he can go 25,000 miles between changes - well, what can I say?

It's not so much that I'm defending this amatuer study, but it really does tell a story that I have actually seen through the years - there are very noticeable construction differences in these filters. If I know about these differences and I have a choice, I will not use the inferior product. I do respect the viewpoint that calling this or the 15 year CR report subjective might be an overstatement, but the bottom line is that the guy simply made a report about what he observed.

 

[reedfish1954]

ONE problem. Let's say your study is correct. Now, try to find the best oil filter to fit your tractor. Fat chance, since TSC carries a Fram oil filter that fits My Kubota B-2150 HST at 2.97 and I change my synthetic Rotella 5w-40 every 25 hours. Did you do a study on Kubota's oil filters at 12 bucks per filter at the dealer's parts counter????

 

[bgott]

Why do you change your oil every 25 hours?

 

[Surge]

Just a thought... I like many have done quite a bit of looking at filters, comparing cost vs. "quality", and I have looked at the filter study a number of times. I currently have 6 vehicles and 1 tractor that I change the oil on. Mainly to save money, secondly to make sure it is done correctly and with quality parts and last because it seems to be somewhat of an obsession oop's, I mean "hobby".

Well, after really looking at the difference in price between a perceived inferior filter and the expensive ones, it was only a couple of bucks... if that on certain sizes. So, I have been using the WIX/NAPA filters and Purolater regular and Pure 1. It's interesting to note that these filters just feel more substantial when you pick them up... Well, for some time I have been looking at the Baldwin Filter's which are made by a division of Purolater. The Baldwin Filters are a high end filter, primarily carried by Truck/Fleet Distributors and are used by over the road carriers as well as many commercial applications for equipment etc... I finally bought a Baldwin Hydraulic Filter for my tractor this week and was surprised to find out the cost was actually lower, by about $1.00 than the NAPA Filter I had been using. While I did not need any right now as I have a good stock of WIX, I checked on the filters for several of my cars and found that those were around $4.00 - $5.00. Again, cheaper than the WIX I had been buying at the automotive parts dealer but only slightly more expensive than a FRAM, Purolator, STP, AC etc.. If interested, you can go to their website, "baldwinfilters.com", check your application, cross reference and find a distributor in your area. I would think that if you change a synthetic, every 25 hours, the filter is much less important than if you are using a regular petroleum based oil and going 50 or more hours. A FRAM probably works just fine for that interval, however, for a couple of bucks more, you can do the same thing and get a better filter. I certainly agree, $12 bucks for a filter is a bit steep, but I would think a quality filter can be had for the $4.00 - $6.00 range, which is what the WIX and Baldwin are.

All of this being said, just like a car, if you are going to trade it off in several years, most people do not care... change the oil every 5000 miles or more and who cares about the filter anyway. For me, I generally keep the cars until they have 150,000 or more, so I take the extra time and expense to change oil every 3,000 and use a good filter.

Just another perspective.....

 

[Bayrat]

Reedfish,

My dealer charges me around $7 for the Kubota filter. I read that study this summer and compared the WIX filter I purchased to the Kubota model, it appears to be a WIX. I have a package of Fram filters that fit my truck and the wife's Jeep and I am going to use them for her 3k oil changes as they add up quickly and then switch totally to WIX or Mobil. My truck gets changed only twice a year so I purchased a WIX for that already.

 

[Bayrat]

Just finished the changes, I removed the old Mopar filter and it appears to be a Wix. I put the Fram on and after looking it over again will use the others left in the case for emergency only after this change. The new Kubota filters do not look like the OEM I removed for the first oil change that mirrored the Wix. I could not tell who made it, but there is a spring in the back so I will go to the study site to determine that.

 

[RobertN]

One thing to note too, this guy did this by himself. Yes, a scientific study could have been done, but at what expense? There is the simple expense of the oil and filters. Probably no big deal. But, for analysis, you could tie up a lot of money. Optical and scanning electron microscopes do not come cheap. Even the lab time to use someone elses microscopes is expensive.

I like waht you siad; the guy reported what he saw. If that saves even one engine, then the data was worth it.

 

[Schultz]

Yes, you could tie up a lot of money, but the test for these kinds of filter are usually very simple. These filters are more or less gross particulate filters of around 10µm, since they, all use depth filter medias and not absolute pore size medias. However, they will capture particles down to 1µm. At 1µm they aren’t very efficient and rely on multiple passes to catch the particulate of this size. Purilator and others are now starting to specify what their multi-pass efficiency is a 1 or 3µm. About a year ago, I started buying the Purilator Pure One for this very reason. I did find the study convincing enough that I won’t buy a Fram filter again.
Being a product development engineer for filters, electron microscopes are mostly for the marketing/sales types and the people developing the filter media. You have to physically test the performance of the final pleated products. Testing & viewing flat stock will not provide same information, because pleated filters perform very differently and have many problems of their own. When developing a liquid or air filter with depth media we use a few simple tests, two of them do involve some expensive equipment. The first utilizes a particle/sizing counter, this provides information on how efficient your filter is at particular particle sizes. Using the same filter material, you can increase its ability to capture smaller particles by just adding some pleats to the filter pack. However, there is a point when the pack becomes too tight and flow is then restricted. The next and most used in both development and manufacture is bubble point. The filter is wetted with a solution, typically water for large pore sizes, alcohols for smaller pore size. Then air is applied to the filter pack by slowly increasing the pressure from 0 psi. When bubbles begin to appear the pressure is noted. This pressure can be correlated to the largest pore size and will show if there are any problems with, filter media, pleating, seam seal or the end caps. The third test we use towards validation and possibly as a QA, check is the bead test. This type of test is typically used for laboratory type filters, because the beads are quite expensive. The filter is challenged with a particular bead size in solution that it should stop. Then the liquid filtrate is put through a particle size counter to find its efficiency.