Hi all. I'm new to this forum as far as posting, but have been a reader since purchasing my CX-9 new in 2012.
I do all the maintenance/service within my capabilities to all my vehicles, and have always been a stickler for keeping clean fluid in their transmissions. That diligence has served me well with three Hondas reaching over 200K with no tranny issues, and two Dodges, one with 230K and one with over 150K still shifting like new. (Too many vehicles, I know.) I like the Magnefine filters. I put them on my Hondas and have NO regrets.
So with this CX-9 I was concerned with having no dipstick to check the level and condition of the transmission fluid. But having read an excellent post by cpb406 on this forum on a "how to" for a drain and fill on a CX-9, I performed the task quite easily. I just want to add to his details, include more pictures, and also show how I added a Magnefine external transmission filter.
My CX-9 reached the 30K mile mark, so I knew the tranny fluid was due for some attention. Having first warmed up the engine and transmission, driving it onto ramps, and letting it cool somewhat, I removed the transmission drain plug in two steps. First using a T40 Torx bit, remove the inner plug.
I probably got about a quart of fluid with this first plug removed. Then using a #17 hex bit, remove the larger/outer part of the plug. That's where you'll get the remainder of the fluid. In all, I got about 3.5 quarts out of mine letting it drain for a good 30 minutes. I was a bit surprised at how brown the fluid had gotten in just 30 thousand miles. Mazda's "good for the life of the vehicle" statement doesn't mean a thing to me.
With it drained, I then installed a Magnefine in-line filter on the return line rubber hose from the radiator internal cooler to the transmission. I had to loosen and peel back part of the protective plastic webbing on this hose, and cut out 2.75 inches of the hose. A Magnefine filter with 3/8" inlet/outlet was simple to then install with hose clamps. Pay attention to the direction of flow arrow on the filter. You want it aiming toward the trannny.
I then reinstalled the two drain plugs, and proceeded to refill the transmission. As noted by cpb406, the fill plug is on top of the transmission below the air filter box. It would be easiest to get to if you do as he states and remove the air box, but I did not. I used a series of 3/8" wobble extensions to reach the plug successfully. You'll need a T55 Torx bit to remove it. Sorry the pic is sideways.
Once I had the plug out, I used a funnel with a long hose to reach the fill hole, and added fresh Mobil ATF 3309. I simply added back the exact amount that drained out - 3.5 quarts.
A simple procedure that I plan to repeat every 20K miles from here on. By the way, I bought a case of Mobil 3309 from Amazon for under $70. I also got the Magnefine filter from Amazon for about $15.
I do all the maintenance/service within my capabilities to all my vehicles, and have always been a stickler for keeping clean fluid in their transmissions. That diligence has served me well with three Hondas reaching over 200K with no tranny issues, and two Dodges, one with 230K and one with over 150K still shifting like new. (Too many vehicles, I know.) I like the Magnefine filters. I put them on my Hondas and have NO regrets.
So with this CX-9 I was concerned with having no dipstick to check the level and condition of the transmission fluid. But having read an excellent post by cpb406 on this forum on a "how to" for a drain and fill on a CX-9, I performed the task quite easily. I just want to add to his details, include more pictures, and also show how I added a Magnefine external transmission filter.
My CX-9 reached the 30K mile mark, so I knew the tranny fluid was due for some attention. Having first warmed up the engine and transmission, driving it onto ramps, and letting it cool somewhat, I removed the transmission drain plug in two steps. First using a T40 Torx bit, remove the inner plug.
I probably got about a quart of fluid with this first plug removed. Then using a #17 hex bit, remove the larger/outer part of the plug. That's where you'll get the remainder of the fluid. In all, I got about 3.5 quarts out of mine letting it drain for a good 30 minutes. I was a bit surprised at how brown the fluid had gotten in just 30 thousand miles. Mazda's "good for the life of the vehicle" statement doesn't mean a thing to me.
With it drained, I then installed a Magnefine in-line filter on the return line rubber hose from the radiator internal cooler to the transmission. I had to loosen and peel back part of the protective plastic webbing on this hose, and cut out 2.75 inches of the hose. A Magnefine filter with 3/8" inlet/outlet was simple to then install with hose clamps. Pay attention to the direction of flow arrow on the filter. You want it aiming toward the trannny.
I then reinstalled the two drain plugs, and proceeded to refill the transmission. As noted by cpb406, the fill plug is on top of the transmission below the air filter box. It would be easiest to get to if you do as he states and remove the air box, but I did not. I used a series of 3/8" wobble extensions to reach the plug successfully. You'll need a T55 Torx bit to remove it. Sorry the pic is sideways.
Once I had the plug out, I used a funnel with a long hose to reach the fill hole, and added fresh Mobil ATF 3309. I simply added back the exact amount that drained out - 3.5 quarts.
A simple procedure that I plan to repeat every 20K miles from here on. By the way, I bought a case of Mobil 3309 from Amazon for under $70. I also got the Magnefine filter from Amazon for about $15.
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