First Auto Tranny Fluid Change at 95k (2015 CX-5)

anyman

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Mazda CX-5 GT
2015 CX5 GT. I'm one of those that bought the "lifetime fluid" claim and never changed the tranny fluid. I wised up recently and just did a drain/fill this past weekend. I have about 95k miles on the car. I got out about 3.3 quarts. Transmission feels fine...doesn't feel any better or worse.

My question is should I do additional drain and fills to try and get out as much of the old fluid or leave it at just this one fluid change? I'm getting conflicting advice...some say to just do this single drain/fill and leave the older fluid in. Others say to try and get out as much as I can.

With 95k miles on the car, what's the conventional wisdom here?
 
How did the fluid that was drained look?
If it were me I'd contnue since you're already invested.
Definitely dirty…like black (dark brown when on a white paper towel).

I just keep hearing the warnings of draining too much fluid and losing the “good debris” from the clutch material in the fluid and then your tranny starts slipping…is there any truth to that?
 
Definitely dirty…like black (dark brown when on a white paper towel).

I just keep hearing the warnings of draining too much fluid and losing the “good debris” from the clutch material in the fluid and then your tranny starts slipping…is there any truth to that?
I did mine at 150K , the fluid was dark brown. I didn't see "good debris" or bits of black clutch material in the fluid which I take as a good thing, I'm glad I changed it, i will keep changing at 50K intervals. I think there is some truth that transmission starts to slip if the fluid that comes out has clutch material. Never flush even if dealer tries to convince you otherwise, the flushing clogs up small passageways in the transmission flow and really screws things up, just fill and drain and you're set.
 
Your single drain and fill is a good move! Sorry to say though that you won’t find any facts or proof of 1, 2 or 3 drain and fills being better or not at your mileage.

What is known though from the few used ATF analysis reports shared here is that the SkyActiv transmission generally generates much less metal in the fluid vs a standard transmission. Not sure if that’s true of your particular transmission without a sample, but it’s something.

The Car Care Nut preaches the one drain and fill theory, saying that you don’t want the fluid too old or too new. You want as constant a state of particles in the fluid as possible. However, the Toyota manual clearly prescribes three drain and fills for severe service for the model he was discussing (latest RAV4 gen). I did 3 drain and fills at 50k and 100k on my 13 CX-5 and the ATF analysis looked really good at both mileages.

Was it the right move? Who knows.
 
That lifetime fluid is nonsense. On a normal driving car. They’ve developed the fluid to last up to 100,000 miles but that’s for a granny drivers. After you hit the 100k miles it’s always recommended to do it every 50,000 miles assuming you’re not towing or driving aggressively. Most engine/transmission/rear end diff failures come from not changing fluid frequent enough based on driving styles and if you live in the desert or places with lots of sand and lots of heat.

I bought my car CPO so I’m following the owners manual but I can assure you once the warranty is up I’ll definitely be doing tranny and the rear and fluids at minimum.
 
@ruthrj Thanks for the insight. I think I'm going to hold off on doing any further drain/fills. You're right about the car care nut. He even thinks it's useless to change your tranny filter as it doesn't get that dirty and like you said, he preaches leaving some of the old fluid in there on older transmissions vs. trying to drain all of the old fluid out. We may only keep this car another 20k miles at most so maybe it's not even worth doing another drain/fill.

@acidbug Yeah, I was always skeptical about the lifetime fluids but over the years I lost interest in cars and maintaining them myself up until recently. When I asked the service advisors about it they simply replied that "they're lifetime fluids and don't need to be replaced" and I left it at that.

After doing a lot of research it sounds like I'll be doing drain/fills at least at 60k on any new vehicle we get.
 
I usually have ATF drained-n-refilled every 30k to all 4 Mazdas I currently own.
Dealer charges about $250 to $300. Or, you can DIY to save $$$.
Mazda sells a kit for ATF change.
 
after If you beat on the car constantly, or off-road not jeep off-road/ doing donuts, and I would definitely recommend constant changes, changing the fluid, at least every 30k n to 40 miles and be sure to check the a treat yes also, runny. (5k miles )Full system oil. I personally put some Lucas oil to make sure the car dip drip. I add.
Also, I put redline
In the summer months..

The front shop bar helped with sliphhty tightening up the grip on the steering wheel. Next up I’ll be doing the front and rear bars.
 
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With 95k miles on the car, what's the conventional wisdom here?

Wise, IMO, to swap in fresh fluids for the "lifetime" items (transm, diff, etc). Have done this on every vehicle I've owned. Wouldn't do it any other way.

I've a hard time believing gearing fails to work better and last longer with fresher fluid.

IMO, the transmission and diff fluid changes ought to be done in the 50Kmi range. Probably a bit more aggressive than needs to occur, but that's better than too late.

On my 2016.5 CX-5 GT, I've also done the swap. Will do them again at the +50Kmi spot (from the last swap). Might get a fluid analysis at the next swap, as a check.
 
I recommend magnetic drain plugs this way. You’ll have an early sign that there are problems. I know for certain there is one for the oil pan but I’m not sure about the tan and the rear end.
 
I recommend magnetic drain plugs this way. You’ll have an early sign that there are problems. I know for certain there is one for the oil pan but I’m not sure about the tan and the rear end.
No, none of the factory drain plugs mentioned including the one on engine oil pan is magnetic. The black part on top of the oil pan drain plug is only the paint. There’s a magnetic disk which sticks on the ATF pan inside though.
 
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Could not find OE ones, but here is an aftermarket kit (filters and gasket).
1695941190253.png
 
Yeah Mazda has never offered any “kit” for ATF change. And Mazda doesn’t even use any ATF pan gasket. In addition, 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. 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 cylinder deactivation. Hence for 2018 CX-5 or newer using the RTV for the ATF pan could be the only option at this time.

CX-5 Transmission: Drain and fill vs flush vs oil pan drop drain/fill?
 
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Definitely dirty…like black (dark brown when on a white paper towel).

I just keep hearing the warnings of draining too much fluid and losing the “good debris” from the clutch material in the fluid and then your tranny starts slipping…is there any truth to that?
The OEM Mazda fluid is not red, it is a dark color, almost black. I have 155k on my 15 CX 5.
Did a drain and fill at 50k, a filter change at 100k, and another drain and fill at 155. Always OEM fluid. I caught about 1 quart of the fluid, when it was draining, in a measuring cup. The fluid looked clean, There was no contamination in the bottom of the container. I will do another at 200k.
The hard part is getting the air filter housing out to get to the fill port...lol
 
I would drop the pan and clean out the magnet, plus change the filter. The magnet catches metal particles, like the clutch material.

I did a drain and fill at 25k. Then another drain and fill at 50k. Then I did the pan removal and filter change at 53k. There was definitely material on the magnet, so it needed cleaning. Once the magnet gets overwhelmed with material, it cannot work like it should anymore.

Stinks that Mazda doesn't use a gasket, one has to use RTV on the pan. It's messy and time consuming as you have to wait for it to set up before pouring fluid back into it. Next time I drop the pan, I will just replace it with a new pan as cleaning off the old RTV is a pain and the pan is really thin flimsy so I don't trust it sealing as well if I have to pry it off to remove it off the trans case.
 
The "lifetime" fluid claim is just a marketing/EPA claim. Lifetime means the lifetime of the warranty, once that expires, the manufacturer could care less if the trans fails. No hydraulic fluid that is subjected to heat and friction will last a "lifetime". Excavation equipment uses similar hydraulic fluids like a transmission does. Those fluids break down and get dirty over time. They need replacing.

Even hydraulic brake fluid needs replacing as it gets dirty, absorbs water, etc.

With synthetic trans fluid, I think 60k is it's service life time and it should be replaced by then. Conventional trans fluid, I would usually change it around 30k on my other cars. If you tow a lot, drive on steep hills, or drive in the hot/dusty desert climate. That can alter the service life of the fluid.
 
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I just keep hearing the warnings of draining too much fluid and losing the “good debris” from the clutch material in the fluid and then your tranny starts slipping…is there any truth to that?
Let's just take a moment to think about this, and clear up the horrendous amount of misconception floating around this topic.

It is "normal" for fine metal shavings to break off parts of the transmissions internals during the initial wear in process. It will continue to occur throughout the operational lifespan of that transmission. There is a strainer (filter) in the bottom of your transmission pan designed to STOP these metal shavings (which turn into a fine metallic paste) to continue circulating throughout your transmission. There is also a metal magnet sitting at the bottom of the pan, designed to catch whatever shavings indeed did make it past the strainer and magnet.

When a transmission is essentially on its last legs (after 250,000KM+ of operation on the original fluid and strainer/filter), clutch packs inside your transmission may start to use some of this debris to produce enough friction to bind together, and yes, draining this fluid and perhaps even changing the filter will very possibly send an almost dead transmission to the grave... This is why we regularly change and replace fluids and filters... designed to be replaced... Long before anything starts to severely break down and approach failure.

In short, engineers place cautionary measures in the bottom of every automation transmission pan to SEPERATE this debris from circulating inside your transmission. Keep it that way. Change the filter/strainer as well.

My Skyactiv AT has more than 306,000KM on it. Regular fluid and filter changes. the transmission, including the valve body and solenoids are all in fantastic condition for the original components and will continue to be for longer than I will ever drive the car. Take care of your transmission and you won't ever have to worry about it.
 
That lifetime fluid is nonsense. On a normal driving car. They’ve developed the fluid to last up to 100,000 miles but that’s for a granny drivers. After you hit the 100k miles it’s always recommended to do it every 50,000 miles assuming you’re not towing or driving aggressively. Most engine/transmission/rear end diff failures come from not changing fluid frequent enough based on driving styles and if you live in the desert or places with lots of sand and lots of heat.

I bought my car CPO so I’m following the owners manual but I can assure you once the warranty is up I’ll definitely be doing tranny and the rear and fluids at minimum.
Honest question here. I'm new to this forum, but had my 2016.5 Mazda CX-5 AWD Grand Touring for over a year now..bought used. Has 110,000 miles, no issues.
I'm ready to change rear diff and transaxle oil, which I'll do myself. I'm hesitant about the transmission oil though, if dealers and mazda don't recommend it.
If some of you are so confident with it's benefits, why wait until the warranty passes? There has to be a reason why it's not recommended? Oil obviously doesn't last forever, but perhaps they think it will last 300k miles?
Why should I trust mechanics and backyard mechanics over Mazda's engineers?
 
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