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Transmission service intervals on "sealed" transmissions - Mazda CX-9

I recently bought a 2011 Mazda CX-9 and love it.
One of the first things i noticed after i got home, was that it did not have a dipstick on the transmission to check the color or level. Now I generally keep my vehicles for 8-10 years so this is sorta new for me.

I first looked in the owners manual but it doenst have any mention of the transmission or service schedule.
So i called Mazda USA, and two other dealers…and got 3 different answers. Please help…

Mazda replied in writing that this is the first year for the CX9 to have a “sealed” transmission…no dipstick. Mazda says this is a sealed transmission and does not need to be serviced.
Dealer #1 said to come in at 30k miles and they would flush it for $200.
Dealer #2 said to come in at 90k miles and they would flush it for $200.

So…what is the recommended service intervals on these newer “sealed” transmissions. From what i hear allot of different vehicles have been doing this for years…just new to me. I’ve had honda’s in the past and im used to a drain/fill every 30k miles.

Which brings up my second question…drain/fill or flush? I’ve never had a transmission flushed…always drain and fill.
I’ve heard stories about the flush causing problems. And what about the magnet on the drain plug. When i do a drain and fill, i always clean the magnet of any debris and inspect for shavings. When i asked the dealers about this, they said that they do not remove the drain plug…the machine will “flush” all the bad stuff out. I guess im just old-school…any opinions on this. (drain fill vs flush)


You’re thinking the right way - manufacturers and dealers both are quite screwy about transmission service. Of course, who will be standing there with checkbook when the thing goes? The dealer gets to receive the check.

I don’t know this transmission’s specifics, but the ideal would be that it has a removable pan with a serviceable filter underneath in which case you’d have pan/filter service done every 30K. If it only has a drain plug without a serviceable filter a simple drain & refill would be fine.

If none of the above I’d go with Dealer #1.

I dont know off hand which transmission is in this vehicle, never looked yet but normal servicing guidelines is to drop the pan, change the filter and refill every 25-30k miles regardless of what the owners manual says. There is no such thing as lifetime fluid. You have a nice new vehicle, maintain it properly and it should last you a long time. Routine maintenance is not expensive, replacement of these components is. Good luck with it.


“Sealed” transmissions and “lifetime” fluid mean what they say. They last as long as they last, then you replace the transmission. Of course, if you can find a way to maintain it, it will last much, much longer. I would take the car to a trusted independent transmission shop and work with them to figure out a way to maintain this transmission. If there is no pan to drop and no traditional way to fill it (neither would be surprising), flushing it may be the only way to maintain it. If that’s the case, you may try shopping around because $200 sounds a little on the steep side for this service. Many independent transmission shops own flush machines and can probably take care of you for less than the dealer can, and probably do a better job as well.

I believe that most horror stories with the flushing pertain to those who wait until the transmission is slipping or clunking THEN flush the fluid. At that point, the tranny was already on it’s way out, but they didn’t know that, so they blame the flush for the problem