Transmission fluid change without filter replacement

Good morning,

This is my first post on the forum.

A little perspective on my car.

We own 2017 CX-5 Touring AWD, with 40,xxx miles. So it has been driven more than average, with mixture of long and short distances. My wife commutes to work daily with 1 mile drive 😊.The car is garaged, and we live in small town. So heavy stop and go traffic does not exist. The car is in excellent shape both visually and mechanically. My wife likes it very much!
Except for 2 dealer free oil changes, I have done all the service myself. I stick to 5000 miles service intervals.

I would like to share my observations and experience while performing the transmission fluid change along my 40,000 mile service. I know that the service manual does not specify intervals for this job, but I have done it anyway since there is a fill and drain plug, and Mazda sells filter and appropriate gear oil.

1. The old transmission filter looked really clean.
2. The transmission pan magnet had ZERO, I repeat ZERO metal shavings. The bottom pan was really clean.
3. I have installed a new filter, put the new RTV gasket, bolted the pan (6 ft lb), and let the pan sit 24 hours to cure before adding the oil.
4. I have drained about 4.5 quarts of the Mazda OE oil, so I have refilled the transmission with the same amount. The old oil looked OK.

IMO, this is not a difficult job at all. Breaking the old seal took some time (putty knife works really well), and the Goo Remover was really helpful in removing some old gasket on the pan. While you are there you can change the engine oil and do the transfer case fluid change as well.

Now the question is, whether this is worth doing of not? I am glad I did it, and it only cost me about $120 for the fluid, filter, and RTV gasket maker. For the next service, I will wait until 90 or 100K miles. Based on condition of my old transmission filter, and lack of metal shaving, maybe drain and fill is a way to go, who knows.

Cheers,
Jarek
 

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4. I have drained about 4.5 quarts of the Mazda OE oil, so I have refilled the transmission with the same amount.

Did you measure the level on the dipstick? Most have found levels to be low from factory such that a simple "same amount" replacement doesn't really work on the first change.
 
I don't plan on ever doing a fluid change. The more I learn about modern transmissions the more I realize why they are in fact lifetime fills. We are lucky to put 10k/year on. I highly doubt I'll have this vehicle 15 years in the worst area of the rust belt in the country. Seems like a waste of time frankly. I used to think oil needed changed every 3k or 3 months too...
 
Yes, I have measured the level with the dipstick before and after addition. Plus I have measured what I have collected which was 4.5 quarts.
 
Yes, I have measured the level with the dipstick before and after addition. Plus I have measured what I have collected which was 4.5 quarts.

where was the level on the dipstick showing before and after? was this cold or warmed up?
 
Good morning,

This is my first post on the forum.

A little perspective on my car.

We own 2017 CX-5 Touring AWD, with 40,xxx miles. So it has been driven more than average, with mixture of long and short distances. My wife commutes to work daily with 1 mile drive ��.The car is garaged, and we live in small town. So heavy stop and go traffic does not exist. The car is in excellent shape both visually and mechanically. My wife likes it very much!
Except for 2 dealer free oil changes, I have done all the service myself. I stick to 5000 miles service intervals.

I would like to share my observations and experience while performing the transmission fluid change along my 40,000 mile service. I know that the service manual does not specify intervals for this job, but I have done it anyway since there is a fill and drain plug, and Mazda sells filter and appropriate gear oil.

1. The old transmission filter looked really clean.
2. The transmission pan magnet had ZERO, I repeat ZERO metal shavings. The bottom pan was really clean.
3. I have installed a new filter, put the new RTV gasket, bolted the pan (6 ft lb), and let the pan sit 24 hours to cure before adding the oil.
4. I have drained about 4.5 quarts of the Mazda OE oil, so I have refilled the transmission with the same amount. The old oil looked OK.

IMO, this is not a difficult job at all. Breaking the old seal took some time (putty knife works really well), and the Goo Remover was really helpful in removing some old gasket on the pan. While you are there you can change the engine oil and do the transfer case fluid change as well.

Now the question is, whether this is worth doing of not? I am glad I did it, and it only cost me about $120 for the fluid, filter, and RTV gasket maker. For the next service, I will wait until 90 or 100K miles. Based on condition of my old transmission filter, and lack of metal shaving, maybe drain and fill is a way to go, who knows.

Cheers,
Jarek

Thanks. Hearing about the lack of deposits in the pan at 40K is very useful information.
 
I don't plan on ever doing a fluid change. The more I learn about modern transmissions the more I realize why they are in fact lifetime fills. We are lucky to put 10k/year on. I highly doubt I'll have this vehicle 15 years in the worst area of the rust belt in the country. Seems like a waste of time frankly. I used to think oil needed changed every 3k or 3 months too...

I guess if you only buy new cars that would work. Heck you could buy/lease a new car every single year and never even do an oil change! But what about the next guy to have the car? Meanwhile for the rest of us who keep cars a long time, fluid changes are needed. Lifetime fluid is a ridiculous concept. Any type of lubricating fluid eventually gets dirty and wears out.
 
I bet by 60k, oil analysis would indicate all lubricating additives would be spent. By 100k if not changed....the metal shavings themselves would be the lubricating agents.

I just do drain and fills because I may want to keep the car through 150k miles in severe (desert heat) conditions AND be able to give or sell car to friends/family with added peace of mind.
 
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*.so you guys change out your wheel bearings every 60,000 miles? Does anyone know what the extent of transmission life testing Mazda performed to justify their stance on this issue? I have worked with Japanese engineers before and found them to be extremely thorough when it comes to reliability testing.
 
*.so you guys change out your wheel bearings every 60,000 miles? Does anyone know what the extent of transmission life testing Mazda performed to justify their stance on this issue? I have worked with Japanese engineers before and found them to be extremely thorough when it comes to reliability testing.

Apples to apples, oranges to oranges. Not a fair comparison.
 
I bet by 60k, oil analysis would indicate all lubricating additives would be spent. By 100k if not changed....the metal shavings themselves would be the lubricating agents.

I just do drain and fills because I may want to keep the car through 150k miles in severe (desert heat) conditions AND be able to give or sell car to friends/family with added peace of mind.

Ill take that bet, but it wont be with my fluid, because Im not changing it. Theres no use to at 60k, or even 100k, and its not because Mazda told me so.

Metal shavings as the lubricant at 100k, ha, I needed that laugh this morning.
 
*.so you guys change out your wheel bearings every 60,000 miles? Does anyone know what the extent of transmission life testing Mazda performed to justify their stance on this issue? I have worked with Japanese engineers before and found them to be extremely thorough when it comes to reliability testing.

I once thought that too with Honda but give the Google a look for piston rings/fouled spark plugs on the Odyssey. Give it another look regarding transmission fluid deterioration and how the interval was shortened after release when issues started cropping up.

Mazda fluid gets dirty. Its nothing special. A TSB was even issued to reprogram how the car handles a signal from a transmission sensor. The fluid was getting enough particulate in it that the car would get a CEL. Mazda had to bump the acceptable threshold higher for that sensor. They didnt catch that in testing prior to release.

Drain of fluid through a designated hole in the drain pan and fill through the dipstick is a whole world of difference vs wheel bearings lol. All of that said, its probably just fine for the lifetime of the car for the majority of owners. But draining and filling the ATF a few times while you own it is not much more difficult than an oil change and really isnt that expensive.
 
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I read through this thread and just want to double check the temp change. Should I Check if temp dip stick is right on the 50 C line and then run the car until blue light on dash turns off. then check if dip stick fluid is on the thick middle marker between 50 C and 150 C to check if it was factory undefiled before I change the fluid? my 2015 is shifting rough when cold so wondering if its undefiled and want to do this properly. thanks
 
Youll want the fluid to be at 50 C mark when the blue light goes off or you determine the fluid temp is 50C or higher using a OBD reader. As the temp of the fluid goes above 50C, the fluid level should creep up the stick accordingly.
 
Can anyone confirm, or deny, that there is NOT a small fiber cartridge filter behind the trans cooling lines return cover (part hoses are attached to) in this photo?

dips.jpg
 
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If there is a cartridge filter on the lines that would be news to me. Had one on my Odyssey but not aware of one with Mazda Skyactiv. There is a filter inside of the transmission (more of a screen really). Drain pan needs to be removed to access it though and theres no gasket. Youd have to use silicone to reseal it to the transmission.
 
Can anyone confirm, or deny, that there is NOT a small fiber cartridge filter behind the trans cooling lines return cover (part hoses are attached to) in this photo?

dips.jpg
No. That is an ATF cooler or heat exchanger with engine coolant and ATF circulating inside.


here is the cooler, water-oil

s5NWCUy.jpg


bottom right
uWwdaz1.jpg


Yeah I know your modified ATF heat exchanger would have no coolant flowing as you're going to leave the original cooler hanging with the coolant hoses.

Actually it'd be the best to find some enhanced aftermarket Mazda SkyActiv-Drive ATF/coolant heat exchanger such as this modified 4-port cooler for Nissan's CVT from China. This enhanced heat exchanger has 2 additional CVT fluid ports for an external fluid cooler. For our SkyActiv-Drive a transmission flush is now possible with these 2 additional ATF ports! :)

FclBYWgSR6i._UX300_TTW__.jpg


AbrVJ8spSSWx._UX970_TTW__.jpg


o2hNVBFQR2mC._UX300_TTW__.jpg
 
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