Do low micron oil filters really make a difference?

[Patman]

I was wondering if you guys have seen any evidence at all that having a premium oil filter (that filters 98% of particles 10 microns or larger) works any better at lowering engine wear than a regular OEM filter (which typically filters out 98% of particles 25-30 microns or larger)

Maybe once I've established a trend with the oil analysis results on my car, I will try one of the intervals with a premium filter so I can compare it to my previous results (I currently am using an OEM AC Delco filter on my car)

In the past with other cars I have owned I have always gone for the higher priced filters, I've used everything from the AC Delco Ultraguard Gold, Mobil 1, PureONE and the K&N Performance Gold (this is what is on my wife's car right now, and her car has always run one of these last four filters only) But due to having to do oil changes about every two months now because of my aftermarket warranty, I didn't want to spend $17 for an oil filter, compared to $3 for the OEM. (These prices are in Canadian spacebucks)

I was also wondering if perhaps having such a fine filter might actually mask the oil analysis results? For instance, if one oil doesn't have as good antiwear properties, but the finer oil filter is picking up the smaller particles, how would we know if the oil is really doing a good job or not, since with the finer filters the oil should theoretically be a lot cleaner.

 

[Terry]

This is a good question and I don't have all the answers; but here's what I've found from experience and testing.

You will not be able to filter fine enough to drop wear particles that you can afford to test for. Spectrographic analysis looks at 10 mic and smaller for wear rates. That includes bypass filtration on the vehicle. A stand alone industrial filter by PALL corp. can but most of us don't have access to that technology.

There are many different schools of thought on automotive filtration,depends on the application for where I come down.

For a daily driver trapping 20-25microns and getting a filter that doesn't go into bypass mode everytime the temp is cool or when it pressure surges is very important.

I was not impressed with K&N's new filter when it came out because it is heavy paper media and is efficient to only 98% at 35 microns,50% at 16 microns.So the amount of 10-20 microns particles trapped is not that impressive. Here's the flip side, Most wear paricles that do any real damage are 20+ microns or larger. Flow rate and not going into bypass mode may be more critical to reduced engine wear than the ability to remove fine particles. The smaller debris can be successfully and efficiently dispersed in a high quality lubricant.
Bypass filtration on a automotive application and most smaller diesel trucks is a waste of your money.Sure it filters incrementally smaller particles but you still have to change out the full flow filter or oxidation will increase and TBN will decrease as oil additives are used up by being depleted by the 20+ micron particles still circulating or loaded in the full flow.

I found that there is a balance to found. Spend as little money as you can on a filter that has quality components, synthetic or heavy paper media,good flow rate when the oil is thick, and resistance to pressure surges. OEM except for mopar(fram) will work for most applications.

Remember the air filter is more critical to clean engines than the oil filter. You've already sand blasted the top end of your engine if the air filter is damaged.

If you are racing using a heavier oil filter case and purely synthetic media may be better.

Use the touch technique to ensure your full flow is not in bypass; BE CAREFUL, at operating temp place your hand on the case of the oil filter and note that it is the same temp as the motor oil, if it is markedly cooler it's in bypass for whatever reason and needs to be changed.

 

[Patman]

Thanks for your thoughts Terry! The one thing I like about the AC Delco filter that I'm using (besides the fact that it's only $3!) is that it's a very solid construction. The alternative choice in the $3 oil filter market is the Fram and we all know how terrible they are, with their cardboard endcaps and failure prone bypass valves. Fram touts their 97% single pass efficiency, but never gives multipass numbers, since they are afraid to admit that these filters get considerably worse as soon as oil has gone through them for a few miles.

I agree about the air filters, which is why I don't have a K&N air filter on my cars. I simply feel they allow too much dirt into an engine, just to gain maybe 1 or 2hp at best. I think the foam type air filters are most effective, as they'll trap the dirt while still allowing good airflow compared to paper.

I've always thought that Amsoil's bypass filtration system was overkill for a regular passenger car. The cost and complexity of that system is too much for anyone other than long distance truckers.

 

[Patman]

By the way Terry, which oil filter do you use on your car? And what do you think about using a longer than specified filter? For my Firebird, the stock filter is the PF25, but the PF35 filter also fits this engine and it's about an inch longer. A lot of guys with LT1 engines run this filter, and I'm pretty sure it has the same bypass pressure settings too, the only difference is it has more media. I'm currently running the PF25 though, but I did run the PF35 on my old 95 Trans Am that I had a few years ago and I always ran a larger than stock filter on my 98 Formula as well, since I found the stock filter to be extremely small and that engine has a 5.5 quart oil capacity.

 

[Terry]

Extra capacity is good so I agree with your theory on the AC oil filters.
My choices for oil filters,I use regular AC filters,motorcraft,fleetguard(stratapore). Any synthetic media filter that is well built and cost less than $10.

I let the oil bear the brunt of the work so the filter doesn't have to.

 

[sprintman]

Terry, I'm using PureOne are they OK?

 

[Patman]

I've used the PureONE but the one thing I don't like is that they pack their media real tight to get those good numbers, and it could be a restriction to the flow. I wouldn't feel comfortable running a 10 micron filter that wasn't a fully synthetic media, the paper media just can't flow well and filter that low. So you'll be going into bypass mode a lot when the oil is cold or when driving hard.

What do you guys think of Amsoil filters? IMHO, they are pretty costly for a blended filter media. The Mobil 1 filter is about the same price but yet uses fully synthetic fibers.

 

[Terry]

Pure ONE are fine, sprintman, motorcraft uses the pure one media in a different case and face. The media is a mix ,good filtration with lower capacity. Thats why I recommend motorcraft,better bang for the buck same media. You may not be able to get motorcraft in Oz.
Really guys unless you are racing buy the best quality but don't break the bank doing it. The oil filter is not as critical as the air filter.

 

[Scott_in_WI]

Terry,

You mention that the air filter is more important than the oil filter. Do you have a "favorite" brand of air filter?

Thanks!

 

[Terry]

Scott, I use K&N,and AC paper filters. It really depends on application. I used to be down on K&N for street vehicles built I've had good luck in the last 3 years or so.
Donaldson and Fleetguard are excellent paper and mixed media air filters if they carry your application.

The key is to make sure the filter fits well and that's what killed my use of the Amsoil filters(planar) they would slide right out of the airbox and you'd get no filtration.

There are others that are just fine that are treated cotton or oiled foam.

 

[Scott_in_WI]

Thanks Terry,

I don't post very often, but follow along closely....

Thanks for all of your great advice!

 

[GW]

Patman,

I was told by Champion Labs that the Mobil filter is also a cellulose/synthetic blend.

 

[Patman]

GW, I wonder if that changed recently, because I'm pretty sure it originally started out as a full synthetic media. Do you have the latest specs on this filter by chance?

Right now a lot of guys are getting the M1 filter for just $1.99! Kmarts are getting rid of them in their going out of business sales.

 

[Chris]

I know that the Supertech oil filters at Walmart are made by Champion Labs and are only about $2.00. These appear to be a huge bargin.

 

[GW]

I do not have the specs. written down anywhere, it was a few months ago that I called.

 

[frule]

I have posted this on Edmunds before,but will post it here as I think it is interesting.
My 5.3l GM engine specs an AC Delco PF59.I purchased several at Autozone.They are NOT the same filter as the PF59 sold at some other stores.So there are at least two versions of PF59s.
Then I saw a ST3675 at Walmart(SuperTech brand).It is IDENTICAL to the AC Delco PF59(but painted black).I cut them apart and can tell no difference.The ST3675 even states that it has a "synthetic-fiber-enhanced-filter media".It also says 99% and 98% single and multi-pass efficiencies.All for $1.78.It is made by Champion Labs.
Seems like an awfully good filter!

[ June 20, 2002, 11:54 AM: Message edited by: frule ]

 

[GW]

Terry,

Where did you get this information that says most wear is caused by paticles 20u and larger?
This does seem to fly in the face of the results of a very well-known SAE study which concluded that most wear is caused by particles in the 2-20u range.

Regarding Amsoil air filters - maybe they have since changed the quality as mine fits so tight in the airbox that I thought I had the wrong one at first!

 

[Cooper]

I know this is a resurrection thread......

But, this has some insight from a couple of the long ago guys with some good tech knowledge. Good addition for the threads that are discussing filtration efficiency.

 

[Cadenza]

Thanks. I found it very useful.

 

[Hokiefyd]

I care very little about the rated efficiency. I suppose that I should...that's not just the primary job of the oil filter, but the only job, right?

Still, I see it as a "what is sufficient for the job" thing. I recently built a ramp up into my shed to roll mowers. My "joists" are 2x4s. It's sufficient for the task, which is supporting a
I feel the same about oil filters. There is generally a trade-off between efficiency and capacity. I think consumers, if they really wanted to stop and think about it, should match their filter to their intended FCI, or Filter Change Interval. To be sure, you could manufacture a filter that is so efficient, it'd clog in 1000 miles. And you could also manufacturer a filter that is so inefficient, you'd never clog it. Somewhere in the middle is a good balance.

Domestic manufacturers tend to specify higher efficiency filters and a shorter FCI. Japanese manufacturers tend to specify lower efficiency filters and a longer FCI. Both manufacturers, domestic and Japanese, build engines that run for many hundreds of thousands of miles. I don't think it matters.

The only take-aways that I see are these:

• If you use a lower efficiency filter, don't throw it away after only 3,000 miles, because you're not getting the full life from the filter.
• If you use a higher efficiency filter, don't run it for 15,000 miles, because you're likely beyond the useful life of the filter (unless it uses premium media and is specifically designed for long life).

Anything in the middle is hair-splitting territory, at least in my humble opinion.