2008 transmission fluid and transfer case

bobbyseal

Member
:
Mazda, CX-9, Sport
Hey everyone,

I got 72k miles on my Cx-9 sport. I'm the original owner. I never had the transmission fluid drained and filled. Nor have I ever had the transfer case fluid done. For the most part, I haven't really noted any issues at all. Again, I was just following the maintenance schedule and so I never really thought about changing out the fluids. Otherwise, I have just done oil changes every 5K miles with 5W-20 synthetic.

Anyway, the transmission drain and fill was fairly easy. The 2008 uses a 10mm hex bolt. I removed that and drained a little over 3 quarts out. I used a transmission fluid funnel down the dipstick tube and filled it with Mobil ATF 3309. I basically did the technique shown on this video https://www.youtube.com/watch?v=n0qDo_yJ-74. I filled a quart of fluid and then poured the old fluid into that used container. I got through about 3 quarts and then I filled the remainder into an old water bottle and estimated the volume to put in. Although this model has a dipstick for the transmission fluid, I had a hard time reading it. I think the dipstick tube got wet with the transmission fluid and it was hard to actually get a good reading. Anyway, here's to hoping that what I did was appropriate. I think I'm going to repeat the cycle in a few hundred miles.
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On to the transfer case fluid. This wasn't too bad, but the access is kind of annoying. I appreciate Avidien's write up. I bought the low profile ratchet, the fluid extractor and the hand pump. Getting the nut off wasn't too bad. Those three tools are really vital to doing this job and being patient. It was kind of a pain directing the tubing into the transfer case to extract and to add the oil. I sucked out what I could initially and then added oil until it started to drain out. I then sucked it out again and refilled. Getting the nut back on made me appreciate having that low profile ratchet. I had a ton of sludge on the nut when it was removed.

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We shall see how it goes. I will probably repeat both in a few hundred miles.
 
The 3309 fluid is good, not synthetic, and not long life. It is good to do the replacement. The drain & fill changes about 1/3rd to 1/2 of the total fluid in the transmission system.
 
The transmission fluid was pretty black when it got drained out. As I wrote, I will probably drain and fill again in a couple weeks. It's hard to find the appropriate oil in my area. The local stores don't carry it. So, I just bought this off of Amazon. What kind of synthetic transmission fluid is out there?
 
I changed the trans fluid on our 2010 3 times over the course of 3 oil changes, and that seemed to finally get the fluid to a nice, clean red color. Good luck!
 
Hey everyone,

I got 72k miles on my Cx-9 sport. I'm the original owner. I never had the transmission fluid drained and filled. Nor have I ever had the transfer case fluid done. For the most part, I haven't really noted any issues at all. Again, I was just following the maintenance schedule and so I never really thought about changing out the fluids. Otherwise, I have just done oil changes every 5K miles with 5W-20 synthetic.

Anyway, the transmission drain and fill was fairly easy. The 2008 uses a 10mm hex bolt. I removed that and drained a little over 3 quarts out. I used a transmission fluid funnel down the dipstick tube and filled it with Mobil ATF 3309. I basically did the technique shown on this video https://www.youtube.com/watch?v=n0qDo_yJ-74. I filled a quart of fluid and then poured the old fluid into that used container. I got through about 3 quarts and then I filled the remainder into an old water bottle and estimated the volume to put in. Although this model has a dipstick for the transmission fluid, I had a hard time reading it. I think the dipstick tube got wet with the transmission fluid and it was hard to actually get a good reading. Anyway, here's to hoping that what I did was appropriate. I think I'm going to repeat the cycle in a few hundred miles.
View attachment 215141
View attachment 215142
View attachment 215138
View attachment 215139
View attachment 215140


On to the transfer case fluid. This wasn't too bad, but the access is kind of annoying. I appreciate Avidien's write up. I bought the low profile ratchet, the fluid extractor and the hand pump. Getting the nut off wasn't too bad. Those three tools are really vital to doing this job and being patient. It was kind of a pain directing the tubing into the transfer case to extract and to add the oil. I sucked out what I could initially and then added oil until it started to drain out. I then sucked it out again and refilled. Getting the nut back on made me appreciate having that low profile ratchet. I had a ton of sludge on the nut when it was removed.

View attachment 215136
View attachment 215137

We shall see how it goes. I will probably repeat both in a few hundred miles.

Did you replace the Tranny filter? If so, is it under the black cover at the front of the tranny? I think I can order one from JCW, but I want to be sure it is serviceable before I try to replace it.
 
No need to replace the tranny filter,, just open the drain plug, then replace it, and fill with tranny fluid. Easy as that.
 
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Yeah, no replacing tranny filter. Not really sure how I would do that. I thought that the filter would require some more significant work to get it out. So, I just did a drain and fill.
 
No need to replace the tranny filter,, just open the drain plug, then replace it, and fill with tranny fluid. Easy as that.

I'm thinking about putting an inline filter (similar to an oil filter) from the front hoses that go to the radiator. B&M makes a setup for the CX-9. Would be a lot easier to service and is supposed to filter up to 5x more than traditional tranny filters. Cost is $50, but seems it would be well worth the investment.
 
I'd like to think that it is shifting better now. I hear these occasional rattles when the engine is cold and I accelerate. Not really sure what that is. It tends to go away. I'm not sure what to do about as it's hard replicate.
 
I just ordered two inline filters for the transmission.

I plan to put one on my 08 and the 2011 CX9's I have. Figure I might as well add some filtration to the trannies while I'm changing out the fluid this weekend. Seems like an easy way to keep great fluid in the vehicles and make filter changes a snap from now on. Who knows how long we will keep these vehicles... hopefully a long time left on them both.
 
After 33 years of working on cars, I recently (several years ago) decided to use only factory fluids for everything except engine oil. Ever. There can be slight variations in the detergents, lubricants, and other additives that may eventually destroy the working parts. Coolant is a prime example. Since we rarely change these fluids, I think it is worth it to pony-up to the dealer pricing and play it safe.

As far as the trans fluid, flushing is much better than drain-refill-drain-refill and nearly as easy.

https://www.mazdas247.com/forum/showthread.php?123855296-Home-transmission-flush-success
 
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