Why is our oil filters so small?
 

Any reason apart from fitment that our rx-8's oil filter so small?

At the store, I cross-ref the FRAM equivalent ph6607 while at the same time noticed the ph5343 (fits MX-6 and 626) share the same diameters. The ph5343 is about 1" taller though. Assuming that it would fit, would it be a good idea to use a slightly larger oil filter?

it doesnt really matter. bigger filter = more filter media. but I would say it probably wont improve anything.

If you open a Mazda filter you will find it too have nearly three times the surface filtering area of the Fram version as well as the media flows better.

IMO after opening a half dozen Fram oil filters... Fram filters should not be used in automotive applications.

http://www.knizefamily.net/minimopar...er-fram-xv.jpg

And if you use too big a filter, it will take longer for the filter to fill with oil before pumping oil into the engines unless the filter has a anti drain back check valve (which most oil filters do not). Mazda OEM filters built by Tennex, and Denso have the anti drain back check valves as well as I am sure all the other Mazda OEM filters do. This is why you poke a hole in the top of the Mazda filter before unscrewing it during an oil change... the hole allows the oil to drain out of the filter before unscrewing it.

Some Frams do have anti drain back valves, but they are cheap ass solid plastic, that really does not seal well and still allows most of the oil to drain back to pan after the car has been sitting over night. The Mazda anti-drainback valve has been silicon rubber since around 1999.

Use Mazda OEM oil filters... they should be the only choice for a Mazda engine.

I have been using the K&N filters because I feel they have good quality as well as having a 1 inch stocket fitting which I sometimes have to use.

If you want a larger filter, switch to the filter used by the V6 MX6. Mazda uses the same thread patterns for all filters and the MX6 filter will fit the RX8 and is almost twice the size. For K&N the RX8 filter is a HP1008 and the MX6 is a hp1010.

Mobil 1 oil filter M1-108 is one I use. Size does not matter as long as it meets the capacity of the oil flow.

The K&N filter is made by Champion Labs,(not related to Champion Spark Plugs). and is basically the same as the Mobil1 filter (also built by Champion Labs) and is a considerably older design than the other Champion filters (AC Delco, Car and Driver, Champ, Deutsch, STP) with a Nitrile anti-drain back valve and a simple leaf spring bypass (which may or may not be accurate for high pressure) and very heavy stamped steel case.

Both the K&N version and the Mobile1 version have a media filter area of about 355 square inches.. about 100 square inches less than the Mazda OEM filter made by Tennex.

http://www.knizefamily.net/minimopar...bil1-08-xv.jpg
http://www.knizefamily.net/minimopar...lter-kn-xv.jpg

If you buy the K&N, and like it, you can get the Mobil1 and save the $2 that the K&N charges more when they add the socket nut at the end of the filter.

The RX-8 filter is shared across several models. That is why its so small. One part number = cheaper.

I too use the K&N HP1010.

I use it because of the nitrile bypass and because my oil is considerably cleaner after 2000 miles with it instead of the OE filter.
Completely clean, in fact.
That is the only science I have for it.
I figure that if it is removing the black, it must be removing the bigger stuff too.

hmm... i've been using Fram for my 92x aero and never had any problems. Anyhow, I am wondering if the OE mazda filter that you mention is blue colour or something else?

I use the K&N HP1008 from Summit Racing.
I wonder what the difference is between the '08 and '10.

Size.

^Yup. Just like the Mobil Oil filters ;) I use the big one. Go big or go home :lol:

Most people never have problems that can be attributed to an oil filter, that is why Fram can build such crappy filters and get a way with it. Most Frams are simple paper elements that are epoxied onto cardboard end caps- and seldom (in my experiences opening them) is the epoxy seal very good... leading to the filter not doing its job.

The K&N, Mobil1 and Mazda OEM filters all use a synthetic spun media, which does a much better job filtering.

See a bad oil filter results in long term damage, not short term. So if you are only keeping your car for 30K miles, then get the cheapest ass filter you can buy... because nothing is going to happen in 30,000 miles.

It is the cumulative damage that happens over time. How many dry starts before you start loosing compression? How many little bits of metal that didn't get picked up in the filter is there before the bearings start seizing?? How many particles of broken down oil additives that clumped before you get a valve sticking.

A good oil filter is the difference between 75k miles on a motor and 150K miles... or in the case of a Toyota, 150k miles and 300K miles.

Using a crappy filter is not something that will cause problems in a couple years, but will be related to the motor failing earlier than it otherwise would.

Most Mazda OEM filters are either Blue, Black or Grey depending on who builds it for Mazda. Tennex and Denso are the most common builders of filters for Mazda, but sometimes you see some from Mazda of Europe, which I have not been able to figure out who builds that one yet.

The filter manufactured by Denso is rather unique.

https://www.rx8club.com/attachment.p...1&d=1219426528

For starters, the cartridge has no end caps to speak of. Each pleat is thermally bonded shut at the ends about 3/16" inward. The main reason for this is the narrow core tube, which allowed for very deep pleats and thus a very long filter element. A wide core tube is not needed for such a short filter. The filter does use a plastic bypass valve similar to the Fram filter, however I have never seen this one leak. It is also held in place by a steel clip rather than plastic tabs like the Fram.

Mazda splits their filter into two models...

The B6Y1-14-302-9X (the "X" will be determined by the series revision- "A" is the most common)

and the LF05-14-302X (the "X" will be determined by the series revision- "A" is the most common).

The B6 for engines under 2.0 liters and the LF for engines above 2.0 Liters.

They just started going to the new cartridge style using the L321-14-302-9U. The cartridge filters are simular to what BMW has used for years and does not come in a steel case, but rather just is the filter and seals to be used in a newer reusable case.

Thanks Icemark. I am convinced then. Will likely get the Mazda OE filters!

Those are a pain. I know Jiffy Lube got spanked pretty badly after several engine failures from improper service on those.

Yeah, the plastic filter cases are really easy to cross thread. I think most Mazda dealers are now selling the filter cartridge or the filter cartridge and a new cap, just for those people.

And the O rings really need to be replaced each time, yet most Jiffy lubes don't every replace the cartridge style oil filter's O rings.

What about the Pure One by Purolator? I have heard those are good too - much better than fram.

I too am interested in the Purolator filters. My RX-8 gets Mazda OEM every time, but all the other cars I service are getting Purolators since people don't stock up on oil filters and generally ask me to change the oil on short notice. The auto parts stores are open much later than dealerships.

interesting read. good info Icemark.

I used to use K&N and WiX only.

Like the others have said, K&N has that 1" bolt top which makes filter removal "much easier than using a filter wrench"

WiX has pretty good reputation. I stop using it because I can get it only at a small shop thats not so easy to get to. I used 2-3 I think.

I tried 3 mobil1 filter in my car. so far so good I say. but I got it because Autozone was running a Oil change deal so the filter comes out to be around 5 bux. Which was reasonable.

Im using Mazda OEM right now, cuz at 4 bux each ... you cant go wrong with it :)

might go with Mobil1 again soon. since they're running a deal on it 27 bux 5 qts of Mobil1 + mobil1 filter. not bad IMO.

Or you could get a billet filter with no-bypass valve and <8micron filtration :) and be done with it :)

very interesting read. I've been using OEM or Atkins Rotary filters.
Might look into these K&N

i only use the mazda filters just in case of problems with the warrenty which is out now and the car is in the shop for engine problems that occured after the recall was done and they are talking motor replacement.2004 g.t. 6 speed with the oil change every 3,500 miles or sooner no low oil driving and no trips ever over two hours long.i think it's a flash problem with the oil metering pump that might have caused the problem.oil light on but not low and no check enginge lights at all.but i keep all records of mazda filters and plugs ,gear oil etc.

Are you positive about the quality of OEM Mazda filter? Anyone else vouch for it? Please advise.

Should I change it to K&N next oil change? I have been using Mobil 1 M1-108. Aren't they the same? MM. Please advise. Thanks.