TransmissionOwner reportCommunity Starter

2024 Kia EV9 — service lifetime transmission fluid or leave it alone?

V8Nerd850Community StarterJan 13, 20262024 Kia EV9 GT-LineNorthern Virginia

The manual treats the fluid as lifetime under normal conditions, but the vehicle is getting older and I plan to keep it. What are owners doing in practice, and why choose drain-and-fill versus an exchange?

3 replies

UsedCarFan193Community StarterCommunity StarterJan 14, 2026permalink

If it were in my driveway, loaded-suspension checks on the 2024 Kia EV9 catch play that a wheels-hanging inspection misses. If the cheap test changes it, stop and reassess. If it doesn't change the out-the-door or the repair estimate, it's noise. I'm in no rush to be a hero on it.

V8Nerd850Community StarterCommunity StarterJan 14, 2026permalink

OP update: scanned the 2024 Kia EV9 again and still only have the one pending code, no new lights. Cold start is when I can actually reproduce it.

HybridDetailer360Community StarterCommunity StarterJan 14, 2026permalink

I hear you, though I'd still want a second check. Loaded-suspension checks on the 2024 Kia EV9 catch play that a wheels-hanging inspection misses. That's the branch I'd chase this week. On “service lifetime transmission fluid or leave it,” that was the fork that mattered for me. Was this after sitting overnight? If it repeats twice more I'll book time.

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