FILTER change poll...run em' twice???

[mechtech2]

For those who refuse to re-use a filter:

Note that we all constantly re-use our oil filters, unless we change them at every start up. So the real question is how long are they good for?
Do you change your gas filter at every fill up? Why not? You are re-using a filter.

Oil filters were commonly changed every other oil change, and some mfrs specifically state this today.
Bear in mind that some will go 8,000 or more with synthetic, so why would this not apply to 2 dino changes at 3-4k?
Also, the oil filter may actually be working better as it ages.

If we have an engine that is being cleaned, or has other specific problems, that is another story.

 

[ET16]

I change out a PureOne filter every other time. I think it's more ecological that way. I don't care about the 1/2 qt of dirty oil that's left behind.

 

[sangyup81]

Now that I think about it, the main reason to not change a filter every OCI is to avoid the trouble of taking it out. In a lot of cars, they are mounted in ways that create a mess and use up a lot of shop towels. In some cars, they are mounted in ways that require you to remove something.

If you are going to take it out and drain the oil, you might as well just put a new one in. Saving small amounts of money by wasting significant time isn't economical

 

[saaboc]

Well now...what a great response to my seemingly rhetorical query! I am very impressed with this site & the people here who have genuine interest in things automotive, then actually invest time to help others - seriously!

I value everyone's opinion (esp the funny ones

) - to touch on a few things I've just read;

The M1 filter has synthetic fiber media. Prob only to better capitalize on the benefits of their M1 synthetic oil...but this will also (theoretically) resist potential degradation from sitting in "contaminated" oil...guessing 90 hrs hot (5000mi @55mph) & 26,190 hrs cold (3rys sitting in the driveway -90hrs). I digress.

The engine runs like a the well oiled machine it is. I never make any short trips that'd allow excess unburnt fuel to sneak past the rings or create undue condensation (no rusted out exhaust components either). I hate people who're unwilling to walk/bike a mile or two for eggs, milk &/or a pint of halfn'half...more likely a few lotto tickets - better known as "tax on the ignorant".

Anyway, my car has Bosch LH 2.2 FI which is by no means cutting edge technology, but is still very efficient (unlike my old 8v w/CIS). All related FI components are in top notch cond. I'd be comfortable w/7500 oci's were I able to rack it up in less time.

Removing the filter isn't a messy proposition on any Saab I know of. The classic 900's are probably the worst w/the filter situated a few degrees from vertical, but I manage to spill nary a drop by re-starting the (still hot) eng right aft draining the sump (run no more than 20sec) to blow a little oil off the top of the filter. I find this is good practice for any vehicle to get the maximum amt of old oil out of the motor. There's still a nice warm coating of residual oil protecting eng internals, so this isn't going to hurt anything.

That M1 filter is upside down draining out even now...not that I've made a decision mind you. I have PLENTY of oil filters (x17 or so...mostly Purolator). This subject is less an issue of frugality & more about not unnecessarily contributing to the problem of hazmat disposal. When I bring my used oil to the transfer station, I am aghast & disgusted by the multitude of containers of all description w/so much used oil in the trash. Don't even get me started on all the discarded Castrol/Mobil/Valvoline/ect bottles still containing a considerable amt of perfectly good new oil. People are so lazy! I desist waste & have a depression era mindset on not throwing out anything that still has life in it. I digress again.

I love the idea about sourcing barely used filters from obsessive 2k oci types! Why don't we forward this to Al Gore!? That f'ng moron...I'll stop now.

Is there any hard data out there reflecting the flow rate &/or efficiency of used oil filters at increasing stages of duty/mileage? I'm pretty sure that minimopar study only dealt w/the specs of new filters - when was it last updated?

 

[EagleFTE]

Welcome back. Now we might start talking about the uniqueness of your 3 year, 5K OCI again instead of debating these otherwise basically normal circumstances.

 

[crinkles]

personally i think 10,000 miles on an OEM filter is OK...

But it does feel nice to have it ALL clean at 5,000 miles at the regular OCI. worht the cost? probably not. filters aren't cheap int he rest of the world like they are in the US.

(dino daily driver)

 

[saaboc]

Yes & I'd like to button up the job by tomorrow am...no garage & rain is forecasted. I'll prob err on the side of caution due to the 3yr time span & break out a new filter. Someone talk me out of it!

How do I post photos? I've taken some low res (.3mp) pix worth sharing.

 

[GMFan]

I've re-ran an oil filter once or twice....sometimes the local auto store was sold out of the filter model #.

I just unscrewed it, poured the old oil out, wiped it clean, re-lubricated the gasket and put it back on.

Now, I typically stock up on filters. I try and keep at least one extra filter around for my next change. I usually buy 3 or 4 of them with the case of oil.

 

[Warstud]

Changed my oil out a few weeks back...was running PP with a (OVERSIZED) white puralator filter with 7,500 miles. The filter seemed to be plugged up and couldn't get much oil out.

 

[ledslinger]

Another factor is if the engine in question is easy on oil, or is a sludger. I have no problem with doing two OCI's on my 4 cyl Accords. The change is so easy without changing the filter. Don't even have to jack up the car. I just do this ocassionaly, and usually change the filter at every change.

I have decided to always put a new filter on my 2.7 Chrysler.

 

[kotzy]

Why not save the oil and just change the filter. At least your running the oil thru new media and catching any dirt. As far as the oil additives perhaps they are not depleated. Your saving more dollars this way than salvaging the filter. Just my 2 cents. kotzy

 

[Curious Kid]

Whether a sludger or not, good question. Some manufacturers may say to go 2 oci with the filter, but that may be with that particular engine under "normal" operating conditions. It would be nice to have a filter bypass valve activation light come on for us curious individuals, something like on the big boy diesels (pressure differential switch - whether it's accurate to the filter's...a note to stay OEM).

I think for the general consumer, things need to be as simple as possible...as if the car could take care of itself, how some would suck that up AND a way the manufacturer to charge even more.

It's one's own vehicle, without knowing what the state of affairs are with the engine, quality of fuel and it's filtration, oil quality and it's filtration, oil capacity and it's media/seal/adhesive condition, engine air intake cleanliness, and operating conditions (misfire, compression/blow-by, full warm-up to cold operation duration....)

There's likely a lot of unknowns, and well changing the filter w/oil is just accounting for the unknown. Do so at your own risk, not to say the engine will grenade, but one doesn't partake here if they didn't want to get the most out of things.

Take care all.

PS - I'd refrain from the added waste generation with attempting to "rinse" an oil filter out with a solvent which might attack the adhesives and seals such as the main gasket, bypass and anti-flow back valve. Don't do it.

Another thing about continued high back-pressure use (that which gets the bypass valve to function), is that the high pressure pulses could allow for particle migration through the oil filter's media so I've heard, but I don't know if this happens with all media types or degree. Another unknown.

 

[PurplePride]

I personally could not imagine letting a $5.00 filter sit through more than one change.
I use RP and a Pure One Gold. I'm sure my 7k OCI will curdle blood here, but for me, it took years to mentally get off the 3k OCIs.
Progress

 

[Audi Junkie]

Sorry to be crass, but if you actually cut open some filters and inspected them, your opinion counts a little more.

In the Astra, the cartridge filters are $10. So I changed the original oem oil out, draining it out over the old filter outside to wash it clean. Put it back in and refilled with clean fresh oil. I will do the same one more time, since these are very short ocis. Afterwards, I plan on 6 month synth ocis, using the new filters for a year.

 

[ledslinger]

I perceive a possible misconception. It appears some think an oil filter cleans oil beyond taking out particles above a certain size. Oil filters don't do anything to remove any liquid contaminants, and they take out few of the particles that make oil look dirty.

I suspect that some people's thoughts about whether a filter can go two changes or not is tainted by overconfidence in their oil cleaning ability.

I hear some say instead of changing the oil without a filter change, just change the filter. Like the new filter is going to clean the old oil up better than the first one. Changing the filter without changing the oil would only do any good if the orginal filter was clogged and in bypass mode, or at risk of going into bypass mode.

I doubt that many filters in well-maintained cars that don't have sludger engines, would go into bypass mode due to clogging during two 5-7K OCIs totalling 10-12K miles. I don't believe modern engines produce that many particles that go into filters. That probably is part of the reason filters are trending toward being smaller.

I think running a filter through two changes is better than running oil through double OCI with two filters.

Filters don't miraculously ingest fouled oil and spit clean, contaminate-free oil out.

 

[sidney004]

Originally Posted By: saaboc


Is there any hard data out there reflecting the flow rate &/or efficiency of used oil filters at increasing stages of duty/mileage?


About 30 years ago, I worked at Purolator California, which was at the time their aerospace and industrial filter division as an engineer. I was involved in tested the dirt holding capabilities of some of their filters(the filters were only changed when the differential pressure across the filter reached a certain threshold as indicated by a pressure gauge.)
Obviously, my comments are far from current and do not apply to automotive filters but the efficiency(greater filtration of lower micron particles) most definitely increases with use as the build up of debris on the media convolutions acts as a depth filter. A major failure mode of the filters were high pressure surges(cold start up in automotive)the media was reinforced with stainless steel mesh to prevent this. The media and elastomers are designed to be compatable with the fluid, that is filter design 101 so I would not think that any filter would dissolve after even three years of exposure(unless it is made in China!!)

FWIW, I use an Amsoil EAO filter and run it multiple OCI's to take advantage of the enhanced filtration, not to save money; the insolubles are consistent on my UOA's and when I have cut the filters open and examined(visual not instrumented) them after multiple OCI's(2-3)they did not appear to be anywhere near the end of their service life; very little contamination in fact.

 

[chet2]

i did that with my focus...i left old mobil one filter on after 6k on mobil one then ran another 4200 miles on supertech...but M1 makes robust filters M1 oil and filter can go 10k anyways...the old m1 in filter probabaly was good for engine

 

[chet2]

i would not like going over 12k on same filter, but i see nothing wrong changing filter every other time on 6k oci intervals...i have a pontiac w/ cartridge and i would always change that every oci, it gets pretty dirty even after 5k...i usually go 6k...my mechanic didnt change cart filter but changed oil one time on my sunfire...5k on valv synthetic and 5 on mobil clean so filter had 10 k on it...filter was pretty dirty...he didnt charge me, he just forgot...i noticed when i changed oil again...was not a happy camper...i said nothing, it didnt hurt anything after reading about some of the oci horror stories here

 

[chet2]

i only buy a M1 filter when it is a special w/ synthetic oil...why not, i have a inexpensive car with oil and filter used in vettes...engine looks spotless after 55k under oil cap

 

[saaboc]

Alright, now we're cooking w/gas! I am very encouraged by Sidney004's input & believe that info is directly applicable to what we're discussing. The tone of this thread started out w/the vast majority of BITOG members being opposed to running an OF twice & now it's nearly swung the other way! Who'dve thunk it? Great stuff - when is the forum picnic? I'll bring potato salad

The high pressure surge (aka cold start) putting a strain on filter media is something I never gave any great thought to. Though I always fill a new filter w/oil before putting it on. I don't understand why this isn't recommended in bold print right on the side of all filters. At the very least, everyone should pour in a little oil to wet the medium. A dry filter encountering a sudden flow of cold oil at 40psi would be tantamount to a parachute opening were it not for the reinforcing structure surrounding it. Some filter brands have only a skimpy plastic cage.

Big trucks utilize a flow meter on their air cleaner housings...a dirty filter creates excess suction which pulls the indicator into the red. The oil tank for our furnace has a similar type of gauge attached inline w/the filter (spin on). I wish some engineer (Sidney?) would invent something like this for automotive OF application...I'd buy one & so would everyone reading this, not to mention a zillion other people. Hmm...I've got an idea on how to do this - maybe I'll try to fab it up myself.

I recently freed up some space in the shed by taking an accumulation of x25 (or more) used filters [I do OC's for friends & family] to the local speedy lube (several appropriately labeled 50g barrels in back). I don't trust the burnout running the town transfer station...the trash cans there are always overflowing w/incompletely emptied containers of used & new (!) oil, suspicious oil soaked bags & lots of completely viable blue shop towels some poser wiped his pretty fingers with. I digress...I just wish I had cut those filters open to inspect the innards - I will next time.

Ok - here's my last question for all of you who're willing or tempted to go two or more OCI's on one filter; Baring the use of the dreaded Fram or cheapo STP (Super Tech??? - feel free to chime in w/others), DOES THE BRAND REALLY MATTER? I don't have any way of knowing if the M1 filter in question is any better or worse than a Bosch, Wix, Mann, Mahle, Hastings, Baldwin (prev two being difficult to find) or even the std white Purolator Plus many of us use. Assuming a 5k oci (within a reasonable time span) on a clean running engine, are all "good" quality oil filters safe candidates for re-use?