Is it really necessary to replace your transmission filter if you perform yearly drain and fills? I've been fortunate to have some vehicles that have drain plugs on the auto transmission. I've made it a habit to drain and fill them on a yearly interval (overkill? Maybe?) with very good luck, and have never had a transmission problem. I've also replaced filters on them, but I've never seen a filter that actually looks dirty or like it needs to be replaced. Is it a waste of time to replace the filter?
Is it necessary to replace filter if you do regular fluid changes?
- Thread starter Johnny248
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I always recommend at minimum that you replace the transmission filter at least once if it is an easy replacement just because of age, factory break in materials, etc.
But technically speaking if your transmission filter is clogged your transmission is toast to begin with.
Follow your vehicles specific maintenance schedule in regards to filter changes if it recommends it though.
But technically speaking if your transmission filter is clogged your transmission is toast to begin with.
Follow your vehicles specific maintenance schedule in regards to filter changes if it recommends it though.
To change a transmission filter in vehicles that have one, typically you drop the pan to service. Cleaning the pan and magnet is as important as changing the filter and gives a good snap shot to the overall health.
I don't know your driving habits but instead of annual changes, I would go every 40k-45k miles with a filter change. There will always be wear materials present regardless of doing yearly partial fluid changes. As the filter loads up, fluid flow from the pan slowly decreases and will eventually starve the transmission of lubrication.
If there’s enough wear going on to impede fluid flow at the filter, the damage is already done. Your frequency of fluid changes will allow the transmission to live as long as it possibly can even without the filter change. Been doing transmission fluid extraction and refills for years without dropping the pan to change the filter. No issues…ever.
If you have an external transmission cooler or even in the bottom of radiator with rubber hoses going to it, you could install an in-line Magnefine that easy to replace. It may catch a lot of junk if you also do not have a magnetic drain plug. Many have "non replaceable" mesh screen that make a window screen look like a HEPA filter.
I look at it the same as magnetic drain plugs and Filtermag on my oil filters. If I can help eliminate any particles from circulating it "should" help reduce wear.
Here is a picture of in-line Magnefine from my Pilot and drain plug with only about 30k of use on it and a couple fluid D&F's. YMMV.
I look at it the same as magnetic drain plugs and Filtermag on my oil filters. If I can help eliminate any particles from circulating it "should" help reduce wear.
Here is a picture of in-line Magnefine from my Pilot and drain plug with only about 30k of use on it and a couple fluid D&F's. YMMV.
agreed.
agreed.
that's because they tend to be screens not really "filters".
I always do a pan drop and a filter change whenever that option is available as I will easily get 1.5 quart more of dirty fluid out on the first drain and I get to clean the pan and see the build up on the magnets, I continue by disconnecting the transmission cooler return line and turn the vehicle on & off until clean fluid comes out (usually 12-14 quarts).
When I get a vehicle that is "new" to me, I always do a pan drop & filter change to see the magnets and clean the pan, then since I am almost doing a complete flush of the transmission fluid, I will skip the transmission filter change the next transmission service.
- Initially - Pan drop & filter change - (almost) a complete flush of the system.
- 60k mile service - (almost) a complete flush of the system.
- 120k mile service - Pan drop & filter change - (almost) a complete flush of the system.
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They are better quality filters than they used to be.
I own a 1985 Ford E350 motorhome.
It doesn't get many miles on it anymore, but I changed the transmission oil and filter in it a few years back, & it was pretty coarse screen material from what I remember.
My 2018 F150 10R80 has a much better quality filter.
I changed it out at around 85000 miles.
I read that Filtran says that these filters are 40 micron, which is very good being on the suction side of the pump.
I am doing the pan filter and cvt warmer filter for first time. Starting to notice issue and inquiry set in which the head technician called at home and told me that even using the fluid i do and the 39 fluid changes that eventually the filters will start to have buildup and so we are doing this procedure on Tuesday. Mpg is still 34mpg but he is confident that with this high performance fluid, new filters and a complete drain its possible to get the power and mpg back to where it should be again. Apparently cvt transmissions are hard on fluid and going cheap on fluid and not replacing it religiously is a disaster waiting so i am glad he called. Already had all the gaskets and filters so Im excited and ready!!!
My 13' CRV has an external filter that is a REAL PITA to get at. I changed it one or twice already. Many spill and fills. Then I decided to put a REAL inline Magnefine in an accessible spot. ( Watch out for those knock offs ). So, it's due for a PITA again. I'll get to it. Gotta replace the headlamps 1st. All yellowed and nasty. I'll get to it...Been sayin that more and more since I'll be 59 in a few months. I change my Magnefine's at 10k. They don't tell you when to change them on the box or canister. 614,868k on the almighty K-24 engine
I was going to replace the hazy headlights in mom's 2009 Ford Fusion, decided to try Cerakote, turned out excellent, easy to do, unless you want those rice racer replacement headlights, lol.
Nah, got the headlight assemblies already. Found a quick fix. Mineral spirits and a razor blade. Scraped all that haze off, then Cerakoted them. Not perfect, but better. Recovering from back surgery now. Go thru a few months of physical therapy, and I'll get them in once healed up a bit more. Probably in late October I'll rip her apart.
What is wrong with the knock offs? They appear to be identical. Also, Magnefine recommends 30k on trans, 50k on p/s
I don't trust the knock offs, that's all. Thank you for the info on the 30k interval change on the ATF filter. Do not use on PSF system. Maybe one day I'll install them. Have to recover from back surgery, go thru physical therapy, then do a few jobs on the front burners first. Couldn't do them because of my back. Always something. Don't get old. Slows down you're " to do" list . 1st back surgery was 2020, 2nd was June 2025. Discs are shot. Gotta take it easy or I'll be under the knife again for another disc.........Their putting in Titanium discs. 1 yr full healing process......... Brain says go, body says NO ! 
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Cerakote FTW!
The AW-55 transmission in 4 of my Volvos has an internal filter that requires splitting the cases to replace. And, clearly, I am not doing that. It does come with a magnetic drain plug, though.
So, I have added an external cooler, thermostat and spin on filter for them. I am a fan of the Baldwin B2-HPG, which has an internal bypass.
I started a thread on this, here:
Thread 'Baldwin B2-HPG used as a transmission filter.'
https://bobistheoilguy.com/forums/threads/baldwin-b2-hpg-used-as-a-transmission-filter.384622/
I used to completely flush them - which takes about 12 quarts for the 8 quart transmission capacity, but with the filter, and good quality fluid (AMSOIL or HPL), they don’t seem to get as dirty as quickly.
So, now, the cars are on a 30,000 drain, filter change, and fill. 4 quarts refills the transmission and the filter. Gets about 1/2 of the fluid, but the fluid comes out clear and red (or blue, if HPL is in it).
Here is one of the filters. It’s tucked up against the left front frame rail, in a previously unoccupied space. A bit of a mess when I take the filter off, but easy to reach, and easy to change.
So, I have added an external cooler, thermostat and spin on filter for them. I am a fan of the Baldwin B2-HPG, which has an internal bypass.
I started a thread on this, here:
Thread 'Baldwin B2-HPG used as a transmission filter.'
https://bobistheoilguy.com/forums/threads/baldwin-b2-hpg-used-as-a-transmission-filter.384622/
I used to completely flush them - which takes about 12 quarts for the 8 quart transmission capacity, but with the filter, and good quality fluid (AMSOIL or HPL), they don’t seem to get as dirty as quickly.
So, now, the cars are on a 30,000 drain, filter change, and fill. 4 quarts refills the transmission and the filter. Gets about 1/2 of the fluid, but the fluid comes out clear and red (or blue, if HPL is in it).
Here is one of the filters. It’s tucked up against the left front frame rail, in a previously unoccupied space. A bit of a mess when I take the filter off, but easy to reach, and easy to change.
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