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Do I need a "Mazda" filter?

Time for the 30K maintenance on my Mazda 3. My owner’s manual says I should only use a Mazda air filter or else I could ruin the air flow sensor, but I found an STP one that is supposed to fit my car. Does it really matter if I use a genuine Mazda air filter and if so, can I get it anywhere else besides the dealer? I’d like to install this myself as I’m sure the dealer will screw me on the price if they install it for me.

If you do install it yourself, keep the receipt. If the manual says use their brand, do so, you don’t want to void your warranty.

Total BS…that’s a French term…I forget the exact translation.

Use the STP filter. Mazda does not have a top-secret technique for building air filters.

Google Mazda parts and you will find several places where you can buy Mazda parts. The one I checked, shows only a 10% discount from MSRP, so the savings doesn’t necessarily offset the shipping charges on small orders. It appears Mazda MSRP for your filter is around $17.

[b] owner's manual says I should only use a Mazda air filter  [/b]  

The magic word is SHOULD.

I suspect that line is in your manual because of all the claims they have had from people using K&N air filters that do kill that sensor. As long as you are getting a quality standard design air filter designed to fit your car you should be fine. However if the instructions are not clear as to what “should” means in relation to the warranty, I would use a Mazda filter this one time.

You can buy the filter from Mazda if you like, they have a parts counter. You can also follow jay’s advice and you should be able to get one at discount. After the warranty is up use what you want, but do avoid those K&N filters as they are not going to help you get 12% more power and 16% more mileage. They may damage your MAF however.

You might want to check out the Magnuson-Moss warranty act passed by Congress when Ford was president. Among other things, it stipulates that if a vehicle manufacturer’s part is required to maintain the vehicle warranty, then the vehicle mfr. must supply the part free of charge. You can feel free to buy aftermarket filters for your car. Just keep the receipt if you need it to verify that you have maintained it per the owner’s manual so as not to give Mazda or their dealer an opening to weasel out of any needed warranty work.

Dealer said could ruin, not will ruin. There’s an example of a weasel word! If he said will ruin, then ask him for your free Mazda filter.

I checked out the Magnuson-Moss warranty act and I cannot find a clear confirmation of the above statement. Most of the act is written in legal gobbledegook but my interpretation is that if a dealer-installed part fails, the warranty cannot be voided and the dealer must replace the defective part at his own expense. You will not be given a free air filter unless the current Mazda air filter is a dud.

If we could look into all the filters history, we would probably find that the Mazda filter is porbably made my STP or another well known company.

Voiding a warranty is pretty tough business for any dealer. Besides,the dealer can’t do it, it has to go through the manufacturers rep and still further up that ladder.

First off, Mazda doesn’t make their own air filters. They purchase them from a company that does make air and other filters.

Any quality aftermarket vehicle maintenance component will meet or exceed the OEM’s specifications.

The claim that damage could occur to the MAF sensor? Scare tactic!


Mazda states use a Mazda filter because they want you to buy a Mazda part. But don’t buy the STP either. STP does not make filters and it most likely is of poor quality. Buy a good name brand, I only buy WIX filters. Filters that were good in the past “Fram or Purolator” now days are not good.

All owner’s manuals say that. Ford will say their brand. Chevy will say AC. Toyota will say Toyota.

While the Magnuson-Moss Act does not require manufacturers to provide a written warranty, it provides specific rules when one is provided.

Among those provisions, FTC regulations state: “© No warrantor of a consumer product may condition his written or implied warranty of such product on the consumer’s using, in connection with such product, any article or service (other than article or service provided without charge under the terms of the warranty) which is identified by brand, trade, or corporate name; except that the prohibition of this subsection may be waived by the Commission if - (1) the warrantor satisfies the Commission that the warranted product will function properly only if the article or service so identified is used in connection with the warranted product, and (2) the Commission finds that such a waiver is in the public interest.” (42 U.S.C. 2302©)

They want you to stay away from oiled-element filters. They will coat your MAFS with oil

All car makers recommend that you use their branded filters and the part about ruining the MAF sensor is a disclaimer to cover themselves.
Dealers routinely see vehicles that have suffered problems due to someone using the wrong item and then demanding that warranty repairs be covered for eternity.

You may use any brand of filter you want. STP filters are fine; and in spite of the bad rap being tossed around on the internet, Fram filters are just ducky.

(Also, the dealer is not screwing you on the price because it’s higher. The dealer cost on a factory OEM filter is higher. In one particular case (Subaru) the dealer cost (price paid by the dealer now) on an air filter was near double the retail cost of the aftermarket. Kind of hard to compete with that.)

It CAN NOT void the warranty by NOT using an OEM filter…UNLESS Mazda provides an OEM filter for FREE. That’s FEDERAL LAW.

Any good aftermarket filter will do fine. Mazda does NOT make their own filters. It’s made for them by one or more of the large filter companies. Buy a good aftermaket filter, it’ll be cheaper and as good or better then OEM.

You never can void your entire warranty for lack of a maintenance item. They only can deny coverage if failed item relates back to the improperly installed part.

Many decades ago, IBM had a real sweetheart deal with their customers. Everything had to be bought from IBM, even the printing paper, and it cost a LOT. There was eventually some sort of action taken, and it is now very risky for any company which sells something to require all maintenance and expendables be bought from them, unless they can show there is a valid reason for it, and that is hard these days.

It wasn’t just things like paper. All disks and tapedrives had to be IBM. When IBM lost the suit, other companies started making these products. A NON-IBM diskdrive was about 1/3rd the price of an IBM disk drive.

In order for the dealer to not honor the warranty it needs to be able to present a case that the part you used contributed to the failure at hand. That really is at the heart of the Magnuson-Moss warranty act. If the dealer can provide evidence that not using a Mazda air filter may have contributed to a warranted failure, they can dishonor the warranty.

However, if they deny warranty coverage based on the use of an aftermarket filter, and the manual states that a Mazda filter must be used, then you may end up unable to get the problem resolved under the warranty without an awful experience in pain. My suggestion is to just spend the extra cash and get a Mazda filter. Buy it from the dealer, keep the receipt on file, and if it’s ever a question that can be your evidence.