Is 112k miles too high mileage for a Transmission service?

3rd Drain and Fill

I need to look into that cooler line exchange method y'all was talking about for future maintenance on the Trans. Otherwise, I was thinking (kinda asking too) that a Drain and Fill every 15k miles ensures most of the fluid is replaced every 30k miles, which I thought was like the gold standard interval for maximizing life and performance of any automatic transmission.

BITOG?
 
3rd Drain and Fill

I need to look into that cooler line exchange method y'all was talking about for future maintenance on the Trans. Otherwise, I was thinking (kinda asking too) that a Drain and Fill every 15k miles ensures most of the fluid is replaced every 30k miles, which I thought was like the gold standard interval for maximizing life and performance of any automatic transmission.

BITOG?
15k is probably excessive. You could go 30k or even 50k drain and fills and be fine. You're not likely to need the transmission to make it anywhere near 300k with a Kia 2.4l, anyway, right?
 
Just do drain and fill every 30k miles, Maxlife ATF works great in those transmissions.
If you fill ATF via fill hole on top of transmission you need to remove air box, then you will see two lines next to each other with one having red paint mark and the other with yellow. Red means hot running ATF into cooler, the other is reverse.
 
15k is probably excessive. You could go 30k or even 50k drain and fills and be fine. You're not likely to need the transmission to make it anywhere near 300k with a Kia 2.4l, anyway, right?
You right. 30k servicing should do.

As for how long we'll keep this car, idk. My Intent is for as long as possible, whatever that looks like, however far it takes us. Whether it last 150k or less, or 250k and more.
 
FWIW I drained and refilled my 2023 Cadillac XT4 at 21,000 miles and the fluid was dark and looked like it needed to be changed. I don't know if it was break-in material or whether these new multi-speed transmissions are just hard on oil or both. I will be doing a drain and fill (no filter to change and the Ford 8 speed AWD and FWD trans is basically the same thing) every 20K miles. That seems like a really short interval but I want this car to last as I'm semi-retired and thinking about fully retiring in the next year or two.
 
I kept all the oil that came out of every drain and fill I've done on the Trans so far. I meant to send samples off for analysis but haven't acquired the kits yet.

You'd be forgiven for thinking these were all samples from the same fluid but there it is, 1st D&F of the OE ATF at 112k, 2nd at 115k with about 3.5qts of Valvoline EP ATF, and the third D&F I did at 118k.

I know some people will always say "color/smell aren't indicators of anything" but I'm highly compelled to do a fourth and see what comes out. The fluid sample from the third D&F you can barely see a reddish hue, but it's mostly dark brown.
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I kept all the oil that came out of every drain and fill I've done on the Trans so far. I meant to send samples off for analysis but haven't acquired the kits yet.

You'd be forgiven for thinking these were all samples from the same fluid but there it is, 1st D&F of the OE ATF at 112k, 2nd at 115k with about 3.5qts of Valvoline EP ATF, and the third D&F I did at 118k.

I know some people will always say "color/smell aren't indicators of anything" but I'm highly compelled to do a fourth and see what comes out. The fluid sample from the third D&F you can barely see a reddish hue, but it's mostly dark brown.
View attachment 251427
Wow, that is still pretty dark stuff.
 
I watched the video he posted and it sure looks a lot lighter while he's draining it out.
I think it might have something to do with the lack of a serviceable filter, but I could be very wrong. I'm less knowledgeable on transmissions than I am engines, and even that is only a rudimentary understanding (at least compared to most of y'all)

I do know the filter in these cars are not serviceable due to having no way to access them outside of pulling the transmission. And I can't forget to emphasize, the evident lack of prior maintenance on this transmission, which should have had servicing of some kind (either a flush or drain and fill) before reaching 100k.

I predict, that if after 5 (so two more D&Fs) total drain and fills, the fluid still comes out looking that dark, I'll just have to accept it, but I think one or two more will do it... Idk but we shall see. I'll do it at my next oil change and keep this updated. I hope this has been interesting for everyone who's been coming back. And thank you to everyone for helping me maintain my one and only car!

Other than the apparent condition of even the newly added fluid, the transmission is shifting very good.
 
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15k is probably excessive. You could go 30k or even 50k drain and fills and be fine. You're not likely to need the transmission to make it anywhere near 300k with a Kia 2.4l, anyway, right?
Agree - all the FWD or FWD biased vehicles we owned:
1. Cooked fluid in 30-40k.
2. Easy to change by measurement of drained fluid.
 
I kept all the oil that came out of every drain and fill I've done on the Trans so far. I meant to send samples off for analysis but haven't acquired the kits yet.

You'd be forgiven for thinking these were all samples from the same fluid but there it is, 1st D&F of the OE ATF at 112k, 2nd at 115k with about 3.5qts of Valvoline EP ATF, and the third D&F I did at 118k.

I know some people will always say "color/smell aren't indicators of anything" but I'm highly compelled to do a fourth and see what comes out. The fluid sample from the third D&F you can barely see a reddish hue, but it's mostly dark brown.
View attachment 251427
Why not pay for a UOA? I think you'll be disappointed.
 
You did a great service to a car with unknown maintenance on it.You also did a nice job on the pictures and explanation, thats why we come here,to learn!
I really appreciate that, thank you.

Ive been inspired by YouTubers like ChrisFix and then encouraged by people here, especially keeping records/documenting everything
 
I can't give much advice about transmission fluid changes.

I did had an accountant that worked for me - he bought a new Kia Sportage.

His wife did not drive - so he started the day driving her to work - it was 25 miles north of their home - then 25 miles back home.

Then 75 miles south to his job.

When he got off work he drove the 100 miles to pick up his wife then 25 miles home.

Average day 25+25+75+100+25=250 miles. He filled up with gas every day.

When he bought the Kia the dealership had a special - free oil changes, tires and tire rotations FOR LIFE!!!!!!!!!!!!!

He was getting a free oil change every 3-4 weeks - plus new tires every 6-7 months.

He had - IIRC close to 350,000 miles on it - when he went in for new tires and an oil change.

That was about 70 oil changes 10 sets of tires - guess $20 oil change = $1,400 + $450 tires for a set of tires = $4,500 so $5,900.

He paid $15K for the base model 1998 Sportage

The dealership manager came out and told him WE ARE DONE - this is THE LAST FREE OIL CHANGE and the LAST SET OF FREE TIRES.

He told me he was going to start shopping for a new vehicle - one that offered free oil changes and tires for life.

I left the company before he found one - but knowing him he got it done.
 
Good story. Kia has had some deals over the years for sure. Wasn’t long ago the Toledo dealer had a “buy a Kia get a Kia” deal. Gimmicks like that may sell cars, but make me run for the hills.
 
I can't give much advice about transmission fluid changes.

I did had an accountant that worked for me - he bought a new Kia Sportage.

His wife did not drive - so he started the day driving her to work - it was 25 miles north of their home - then 25 miles back home.

Then 75 miles south to his job.

When he got off work he drove the 100 miles to pick up his wife then 25 miles home.

Average day 25+25+75+100+25=250 miles. He filled up with gas every day.

When he bought the Kia the dealership had a special - free oil changes, tires and tire rotations FOR LIFE!!!!!!!!!!!!!

He was getting a free oil change every 3-4 weeks - plus new tires every 6-7 months.

He had - IIRC close to 350,000 miles on it - when he went in for new tires and an oil change.

That was about 70 oil changes 10 sets of tires - guess $20 oil change = $1,400 + $450 tires for a set of tires = $4,500 so $5,900.

He paid $15K for the base model 1998 Sportage

The dealership manager came out and told him WE ARE DONE - this is THE LAST FREE OIL CHANGE and the LAST SET OF FREE TIRES.

He told me he was going to start shopping for a new vehicle - one that offered free oil changes and tires for life.

I left the company before he found one - but knowing him he got it done.
If it was a lifetime deal it sounds like that stealership should be talking to an AG!
 
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