benefits of larger/dual filters?

[tom slick]

alot of people feel a larger filter then oem specified is beneficial to their engine. with the tiny filter on my 2.0l mazda (i've seen bigger fuel filters) i can see how someone could think that. some people believe that a dual filter setup (normal filters, not bypass) gives even better filtering.
can somebody give me a real reason why a larger filter is better? i understand if you are going to be in very dusty conditions (i.e. tractors) and i understand if you are only going to change your oil every 10k miles.

thanks

 

[mph]

I think the main perceived advantage is that with a larger filter area, there is less restrictive flow across the filter medium. This should result in less oil bypassing the filter.

However, when I tried an M1-105 oversize filter on my Honda, I noticed on several occasions that it was clearly taking longer than usual for the oil light to go out at startup. The filter is mounted on its side, and I'm sure some oil drains out when it's parked for a while. I think I was seeing the delay in filling up the bigger filter, and it made me nervous.

The M1-105 was an experiment, because I got on one clearance at AutoZone (for about $3). I'm not planning on pursuing oversize filters any more.

 

[Pablo]

I have a regular dual (not by-pass) mount on my Volvo.

Large increase in oil volume (from just over 4 qts to 6+ qts) is good, more filter area is good.

Pressure comes up fast.

Worry? If a line goes, shut down fast!! Never had a line go, but it is possible.

 

[unDummy]

MPH, that was the wrong choice for an oversized filter. The M1105 should not be used in place of the M1104. When oversizing, I still say that it better to match(or choose lower) filter bypass pressure.

Pablo, I know someone who lost a line on a remotely mounted full flow filter. It was a sad day for that engine. Then I noticed that the owner used zipties

and not line clamps to secure the oil lines.

I guess that it all depends on the competence of the installation, quality of the component chosen, and consumers research.

Longer drain intervals, larger oil capacity, supposedly less filtering oil flow resistance, supposedly less oil filtering bypass time, are some of the reasons!

 

[Greaser]

quote:

---

Originally posted by mph:
I think the main perceived advantage is that with a larger filter area, there is less restrictive flow across the filter medium. This should result in less oil bypassing the filter.

However, when I tried an M1-105 oversize filter on my Honda, I noticed on several occasions that it was clearly taking longer than usual for the oil light to go out at startup. The filter is mounted on its side, and I'm sure some oil drains out when it's parked for a while. I think I was seeing the delay in filling up the bigger filter, and it made me nervous.

The M1-105 was an experiment, because I got on one clearance at AutoZone (for about $3). I'm not planning on pursuing oversize filters any more.

---

I found that using the M1-204(OEM size) on my 4.0L Jeep motor,which is mounted sideways on the block, a general lag in oil pressure at start-up and the "check gauges" light would come on and a chime was heard...ok...went to the M1-301 oversize....not as often..but was still there...tried Bosch Premium in oversize...WORSE...back full circle to the Purolator Premium Plus in the Ford oversize (L30001)...GONE

 

[labman]

There are many points where I have not seen good data. I think we
all know filters eventually fill up and restrict flow. I don't know how
often it happens if ever with auto oil filters. When Advance Auto
wanted the same $3 for a PF 52 as the for the specified PF 47, why
shouldn't I go ahead and buy the larger? Isn't bigger better? Once
the filters start to restrict flow, a bypass in the filter or engine opens,
and allows unfiltered oil into the engine. That gives some of us here
nightmares. Many of the others here think the same way or are
even willing to pay premium prices for what should be better filters.
Again, a lack of reliable data. I can not point you to solid data
showing your engine will last longer with a bigger filter. Some
people here I respect have suggested the filters normally do little if
anything. I have no good argument to prove them wrong. Certainly
many engines, including my truck for a while, have gone many
miles using the poorly regarded Frams.

As for your tiny Mazda filter, My son left a used B6Y214302 in my
garage. I chopped it open and found it had 121 sq. ins of filter area.
That compares with 84 for a much larger Fram PH 3950. Even a
Super Tech the same size has twice as much as the Fram and the
AC PF 1177 has 3 times as much. No more orange in my truck.

 

[Pablo]

I almost the biggest benefit of all:

Some cars the filter is BARELY reachable, even when the car is on a rack. Relocating the filter is a HUGE plus.
I don't expect you guys to know where the filter is on a Volvo 240 turbo. Let's just say some folks skipped oil filter replacement because they couldn't reach it.

I can sit crosslegged and change my 2 filters now. I grin every time

!

 

[tom slick]

other then just telling me bigger is better, is there a real reason that bigger is better. i seriously doubt that the oem specifies an oil filter that has a pressure difference (delta p for those who are technical) great enough to be of any concern under normal circumstances. i would also doubt that filters on modern engines clog up and bypass. how many people have you seen here that cut open thier filters find tons of stuff in them? (other than engine flush users).

btw i use a remote single filter on my 22r toyota. besides being easier to change and less messy, the new mounting position doesn't drain the filter so i get instant oil pressure.

[ June 14, 2003, 02:25 PM: Message edited by: tom slick ]

 

[Patman]

quote:

---

Originally posted by tom slick:
other then just telling me bigger is better, is there a real reason that bigger is better. i seriously doubt that the oem specifies an oil filter that has a pressure difference (delta p for those who are technical) great enough to be of any concern under normal circumstances.

---

Let's look at this another way though. Do you think the carmakers want your car to last 300k? No. If it makes it to about 150k that's all that really matters to them. So they aren't necessarily choosing the filter which works best for that engine's long life. Which is why we go to such great lengths on here to find out which filters work better than OEM!

 

[labman]

As I said "There are many points where I have not seen good data".
Nobody posted any proof we need bigger filters. Many of us don't
have any proof that there is more filter media in the larger filters we
use. I have compared Fram filters to cereal boxes, large, but half
empty inside.

None of the filters I have chopped open, including the Fram, were
full of crud. However all them were much darker than new ones.
The "dark" is finely divided metal. Each little speck of metal is
plugging a pore in the filter. Bigger filter = more pores = longer
until restricted. I have no proof that the PF 52 I switched to when I
had my Grand Am was any better than the PF 47. It didn't cost
anymore, so why not?

 

[tom slick]

with the 75+ filter designs sitting on the shelves at the local autoparts store i have a hard time believing that the oem designers aren't concerned with filters. if that were so then there would only be three sizes small, medium and large with either a metric or std thread. then we'd only need 6 filters to fit any car. that could save car companies millions.
i can just imagine an engine designer saying to himself "**** this engine lasts way to long in our tests, i guess i'll have to use a small filter on it so that it will trash itself around 100,000 miles"
or
"well shoot, we only have 39 differen't filter designs that will suit this engine's needs, we need to get the public to spend more money, i'll copy this filters specs but make it half as big, that will make the accounts happy"
i am not trying to argue, i am just curious, all of the reasons i have ever heard for a bigger filter is just "bigger is better".
i am hoping that someone can give me a reason why "bigger truly is better." then i'll install filters the size of a 5 gallon bucket on all my vehicles and they'll all last 500,000 miles.

 

[springnr]

Five gallon bucket filter would sure up your oil capacity and more media area should increase flow.

Oil pressure might drop though?

 

[labman]

You have to understand a little of how engineers think, or at least
some of them. They make their living designing new products. Not
only is using an existing oversized filter a waste of money, it
reduces the demand for engineers.

My father in law was in chemical equipment design. For a while I
was managing a small production plant. I remember a discussion of
2 1/2'' pipe. I maintained any engineer contaminating a production
plant with such an odd ball size should be shot. He maintained that
it was bad engineering to go ahead and use 3'' pipe if 2 1/2'' was all
you needed. Bear in mind that all these carefully designed plants
never work right and often have to to be modified. Also as things
change, more modifications are needed. Sometimes in the middle
of the night or weekends when the supply houses are closed.

I am sure GM is buying those (*#$)$%@#$&!! AC 2244G cartridge
filters that cost me $7 much cheaper than a PF 47, and they buy
enough of those PF 47's that they get them cheaper than the
slightly larger PF 52's. Everything is designed with safety margin.
Apparently they are huge in oil filters. I can not prove any problems
from running Frams with 1/3 the filter area of AC''s for years on my
truck. No none of us can prove bigger is better. Still if bigger is the
same price, why not?

 

[Mobil2]

Lots of people have very valid opinions, but I'd also like to see some factual test data that proves an oversize filter has an advantage(s) over a stock size oil filter for any application (preferably Honda thou

).

 

[TC]

Excerpts from a post by "ShootingStar" in the thread "Mobil 1 and K&N Oil Filters":

"Ok, I just got off the phone with Champion Labs again, and I think I finally got some good info from a real car guy...these filters (Mobil 1 or K&N) should only go into bypass when used for long drain intervals 'over 5000 miles' as the media becomes more restricted, even in high reving motors."

This might suggest that, along with other similar authoritative comments on this topic, any quality filter recommended for a particular application -- including the 'lil pup filters one commonly sees these days -- are not likely to clog or constantly bypass if swapped more often than extended 7,500 mi intervals. (Dusty environments are another matter.) In turn, this would suggest that oversize filters might be helpful for peace-of-mind, but certainly not necessary for the vast majority of vehicles. But if you KNOW an oversize will work on your vehicle (correct bypass pressure and anti-drainback features, etc.), then what the heck?

 

[Z Licious]

I, being an engineer designing processes myself, would like to believe that car companies design things like oil filters to work well for the engine and last a long time. Now the engineer may want to do that, but believe me the final decision for a design is always based on COST and generally little else.

If a design for say an oil filter is barely adequate but works and is cheaper they will use it.

For example, I own a 2003 Nissan 350Z $35k sports car. So if Nissan really cared about using a good quality oil filter then why did the car come with a **** FRAM filter on it (Nissan OEM is FRAM)? -- $$$$$

Save a buck on the oil filter and multiply by how many thousands of cars and you get the idea.

There are virtually no mass market products that you can buy that are the "best" or "highest" quality designs simply due to companies trying to optimize profits.

 

[DEWFPO]

I have a dual filter set-up on my truck and I use one tight filter like a Purolator Pure 1 and a loose one like a Motorcraft FL1A. This way I have the best of both worlds. Fast oil pressure build up on start up and great filtering side by side. (I hope)

DEWFPO

 

[Gary Allan]

I use a Chevy style dual oil filter set up ...and I also use the larger 2 quart chevy filters (Napa Gold 1794). This has increased my normal 6 quart oil change to a 9.5 quart oil change. I've noted no increase in oil longevity using these. I'm currently doing a 10K oil/filter with Delvac ...at which time (in 2000 miles) I'll do a UOA. If it proves, as I suspect, that I've retained no extended protection from this current setup ....I'll switch to the smaller filters and just do my 6 month oil changes (the NAPA 1794 cost over $10 each).

Pehaps the addition of the oil cooler that is sitting in my garage collecting dust would help ...but I can't see 9.5 quarts with an aftermarket HV oil pump being "heat fatigued" in this engine (4.0 jeep). This may be a nut that I can't crack ..so to speak.

I noted a measurable fuel mileage increase with Delvac 1 ...this increase disappeared at around 6k into the interval. Then again ..this engine has 76,000 on it and has only had new plugs ever put in it ....so other factors may be contributing to this loss of "gained" fuel economy.