Auto Transmission filter replacement?

curls

Member
I'm planning to use the method where I flush the transmission myself (using the oil cooler line, it's on this site somewhere). Anyhow, is it really necessary to change the transmission filter that's accessible by removing the transmission oil pan? I see NOTHING in the owners manual about the transmission fluid, let alone the transmission filter.

Frankly I'd rather not do the filter as I don't need to drop the transmission pan at all with the flush procedure. But, if it's 100% necessary and if I would be rediculously stupid not to do it, please let me know (with a reason) and I'll pick it up. Unfortunately the filter kit is $35 locally and that's as cheap as I can get it for here in Canada.

Thanks,
Eric
 
Some people say the flush at hi mileage can cause problems. I had mine flushed at 35k with AMSOIL syn atf. I've had no problems but I will be changing the the filter/strainer thing this time at 84k & will be draining 2-3 qts then refill with fresh AMSOIL 2 or 3 times at 1 week intervals instead of flushing the whole thing just to be safe.
 
I'm aware of the power-flushing potential for problems. I'm not using a power-flush machine, however; I am flushing the system using its own power (the oil cooler line that leads from the radiator back to the transmission, as detailed here: http://www.mazdas247.com/forum/showthread.php?t=94623)

The car has 175,000 km on it and has only had a single (3L / 3qt) drain/fill done to it at approx 103,000km.

I actually just spoke with a friend who works at Mazda (parts dept.) and he said that he's NEVER once sold an auto trans filter for the Protege/P5 car, including to his own service department! He says its a "screen" and if you want, can just be removed, cleaned, and put back in place. But even that, he says, is pretty rare to be done even on old transmissions. He says that although Mazda doesn't mention the ATX fluid, he suggests it be done every 100k km / 60k miles just to be sure its in good working condition. This was upon recommendation from the head technician at his dealership.

Good info (to answer my own question, lol!).
 
I did a drain/fill/flush/fill on my P5, what I did is drain the 3.5(ish) quarts of ATX fluid from the tranny pan, then refilled with new ATX fluid. Then I pulled the trans cooler line off the radiator and drained another 3.5-4 quarts from there. I replaced that with new fluid, then drained another three quarts out to fully flush out the old crap and topped the system of with 3 quarts of fresh fluid. I'm going to do the same thing here shortly and replace the cheap ATX fluid I used with Mobil1 full synthetic. I don't see a reason to replace the filter, as it's supposedly just a screen. The only thing I could see dropping the trans pan for is to check for metal shavings on the magnet to see if the trans is getting beat up more than it really should be. My trans fluid was in pretty bad shape when I did this back at about 83,500 miles. Since then my shifts have been much better, so I know for sure it helped a ton.
 
I would definitely change the filter. Very easy and relatively cheap when compared with a new tranny. That filter holds all the crap that runs through your transmission, so might as well get a new one in there to start filtering anew.
 
Ok so I'm currently waiting for the new Ultra-Grey silicone gasket to cure. I didn't change the filter, but I did clean it (ran some ATF through it backwards and forwards, but overall the fluid was darn clear (pink) so I'm not concerned that the filter is dirty or clogged. I cleaned the doughnut magnet thats in the pan, cleaned the pan thoroughly w/ parts cleaner, and once that dried, reassembled everything. In about 30 minutes I have to torque the pan bolts to 9.0 N-m and then I can proceed with the rest of the flush (I didn't want to add new ATF while the silicone is skinning over, or it might cause problems with how it cures. The Ultra-Grey specifically says to wait 1hr before torquing and I'd assume exposing to oil.).

Thanks for the advice everyone!
 
OK, doing the how-to way to be done the same day. Still gonna swap out the strainer since I already have it, also to get a visual on the insides a bit just to check it all out & ponder the Lentech vb upgrade some more.
 
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