CX-5 Transmission: Drain and fill vs flush vs oil pan drop drain/fill?

[sm1ke]

I'd say you're at just the right mileage for a drain and fill, and that's all you should need. There's lots of threads on the subject. You can start here:

https://mazdas247.com/forum/t/atf-drain-fill.123838434/

Only use Mazda fluid.

Thanks for providing a link, @madar.

@q1054521247q, in the future please use the Search function as previously suggested by other members. Thanks!

 

[Lazy2.5]

Goodness me, it's only two years old.
I know someone will argue this one, but I'd leave it alone. Not necessary at this point, unless you are having issues, in which case a fluid change won't fix it.
If you do decide to go ahead, don't do a flush with one of those machines. They do more harm than good. Drain and fill.

My 6 has 296,000KM on it. I have seen what the bottom of the pan looks like in these AT's a couple times now.

Once you have it dropped, you'll be happy you did.

 

[Mazda6Dad]

So I have a 2017 Mazda6, but the process seems the same for a pan drop/gasket/filter replacement and then 3x3 drain and fill. My only question is whether to use the o-ring gasket that come in some kits or just use RTV when replacing the pan? The gasket would be easier, but I don’t trust the quality of the Chinese manufacturers that surely make them.

Anyone have a strong opinion about that?

 

[Lbear]

So I have a 2017 Mazda6, but the process seems the same for a pan drop/gasket/filter replacement and then 3x3 drain and fill. My only question is whether to use the o-ring gasket that come in some kits or just use RTV when replacing the pan? The gasket would be easier, but I don’t trust the quality of the Chinese manufacturers that surely make them.

Anyone have a strong opinion about that?

With RTV, the pan mating surfaces must be completely oil free and clean. The RTV must be applied to make sure it covers the mating surfaces without any voids.

Gaskets are much easier but the gaskets they supply in the kits are usually cheapo gaskets. On my other cars, the factory included a steel core gasket encased in rubber. These gaskets are reusable and I've never had them leak.

Mazda used RTV as it's "less expensive" than a quality gasket. RTV makes it harder later to do service on it as it requires a lot of detail work to remove, clean and reinstall.

I used RTV and hopefully it doesn't leak. So far, it hasn't but I haven't drive it long to make sure it is not leaking.

 

[Jmaz]

With RTV, the pan mating surfaces must be completely oil free and clean. The RTV must be applied to make sure it covers the mating surfaces without any voids.

Gaskets are much easier but the gaskets they supply in the kits are usually cheapo gaskets. On my other cars, the factory included a steel core gasket encased in rubber. These gaskets are reusable and I've never had them leak.

Mazda used RTV as it's "less expensive" than a quality gasket. RTV makes it harder later to do service on it as it requires a lot of detail work to remove, clean and reinstall.

I used RTV and hopefully it doesn't leak. So far, it hasn't but I haven't drive it long to make sure it is not leaking.

The factory rubber /steel core gaskets are nice but it's a bummer to have your transmission serviced somewhere and later find out they tossed the rubber one and used the gasket from the filter kit. Which then leaks later on. This happened on a previous car where I forgot to instruct them to reuse the factory gasket. Dealer price on factory gasket was ~ $50 and this was almost 20 years ago.

 

[yrwei52]

If anyone thinking about using the aftermarket transmission filter with pan gasket, be aware that the gasket may not fit depending on your transmission pan. My guess is Mazda had changed the transmission pan shape when they added the cylinder deactivation for 2018 CX-5, where the transmission was also modified to add some components to fight the vibration by CD.

I did mine today. 2020 CX-5 Touring, 2.5L NA engine, 50,000 miles. ⋯
The WIX filter and gasket I got from Rockauto had a different variation of gasket (similar but 2 holes were about 3/4" off), so I ended up buying RTV from a local auto parts store, I was a bit pissed about that.

I use Wix filters, which includes a gasket. I use the gasket every time, and I've never had a leak.
Wix part number on the filter for my 2013 CX-5 with the 2.0 is WL10379.

Used that same filter today on my 2020 2.5L NA Touring.
Two holes on the gasket were about 3/4" off - couldn't use the gasket. That had me a bit pissed. Ended up using $15 tube Permatex from my local parts store - the price of the RTV was nearly as much as the filter and gasket, which had me more pissed.

And from:

Blauparts.com - Mazda CX-5 Transmission Fluid Change Kit - 2013-23 - 6 Spd - Ravenol

Vehicle Fitment Note: Fits all 2013-2017 Mazda CX-5 models. 2018-2023 Mazda CX-5 models could have two transmission pan types. 2018-2023 Mazda CX-5 model owners will need to confirm a transmission pan part number FZ01-21-51XA, FZ01-21-51XB, FZ01-21-51X, or FZA1-21-51X before ordering. We suggest contacting your dealer and ask them what transmission pan part number you would need if replacing it. You can also visually inspect the pan for an OEM part number sticker but these have typically been weathered and are not legible.

 

[Newtocx5]

Beware of the dealership that quotes you a price for flushing the transmission.

The Skyactive trans cannot be flushed without a special adapter and from my reading on this forum, this adapter is not a common thing, and most shops don't have it.

I suggest that the OP do some reading on this forum as there are several threads that address this.

My dealership gave me the option to do drain and fill or a flush. Assuming a Mazda dealership would have the needed adapter to adequately perform a flush, no?

 

[sm1ke]

My dealership gave me the option to do drain and fill or a flush. Assuming a Mazda dealership would have the needed adapter to adequately perform a flush, no?

It's a safe assumption, but something you'd want to clarify with the dealer first. Just tell them you heard that a special adapter is needed to flush the transmission and ask if they have it.

 

[JonhDe31]

Hello guys,
I had 55000 miles on my 21 cx5 signature now all I have done to the car is engine oil/filter and basic maintenance stuff. With the exception of spark plugs changed at 45000 miles. I have been calling around the dealership asking for AWD fluid change and transmission fluid change. called many different dealerships around they told me many options for transmission service with a wide price range too.

first, is AWD fluid the same as differential fluid? and at what mileage should I get that serviced? all the dealerships I have called, have never done AWD fluid change before. can I do the service myself?

as for transmission fluid. I know and have seen most Asian markets drop the oil pan and clean the magnet/change the filter inside and fill the fluid. But the NA market dealerships told me "It's a sealed unit and can not drop the pan" and they will not drop the pan because they don't want to be responsible for oil leaks later on. so of course I'm not confident enough to do that as well. (I have never done it before. I don't wanna overfill, don't know how to check the level. also never play with RTV before don't want it to leak on me)

option 2 flush costs 300-450. It's a little on the high side. At Asian markets. dealership and local shops do not recommend doing flush because some said "will cause shifting problems like jark.... because it flushes all the dirty particles into gears (but isn't the current oil in the car pushing around those dirty particles around the gears too?????)" now I'm not sure how true that is. But most dealerships here in Texas recommend Flush said it's cleaner and won't contaminate the new oil going in and said to be the best way to replace all the transmission fluid. Normal flush where just replace all old with new oil it's about 300. and Full flush with BG I think its 450.(is that good or not necessary)

option 3 the basic just drill and fluid. cost around 150-200ish. I know this will drain all the fluid but how much will stay in the trans and how much new oil will add?

which option would you guys recommend? I don't think I have enough knowledge to do either option so will probably leave it to the dealership to do with whichever option based on this form.

For the AWD fluid – yes, that’s essentially the same as differential fluid. Most people service it around 50–60k miles, so you’re right on time. It’s a pretty simple job if you have the tools, but since your dealers say they rarely do it, I’d stick with OEM fluid and either do it yourself carefully or ask an independent shop that’s familiar with Mazdas.
For the transmission – the “sealed unit” thing is more of a dealership policy than reality. A simple drain & fill (option 3) is usually the safest bet. You’ll replace 30–40% of the fluid each time, and if you repeat it after a few thousand miles, you’ll gradually refresh most of it without risk. Full flushes can be controversial — some swear by them, others avoid because of the debris issue you mentioned.
If you’re not comfortable doing it yourself, I’d recommend drain & fill at the dealer or trusted shop. Lower cost, less risk, and still keeps the transmission healthy.

 

[erhayes]

I suspect that Mazda has determined, because of individual warranty requests, that many transmissions have been damaged by DIYers, so they don't have a change recommendations. Already on this subject we see people trying to cheap out by not using the OEM fluid. Just my observations. Ed