Sealed Transmisson ATF Drain & Fill : Recommended Change Interval ?

Sep 10, 2010
On 2017 Hyundai / Kia 2.4L GDI 6 - speed transmission it is recommended for "severe service" to perform a drain & fill service at 60K miles (I just did two separate drain & fills at 48K miles 2K miles apart with Valvoline Maxlife ATF) and if normal service then 100K miles is the suggested interval . *I did not see where Hyundai / Kia advise a reoccurring schedule for subsequent drain & fill service ? If I had to guess - driving in your typical mixed city / suburban / interstate driving scenario you would want to do the ATF drain and fill service every 30K ~ 40K miles after the first drain & fill service ? Thanks in advance for sharing your experiences / recommendations .

P.S. I believe a "sealed transmission" guaranteed for life (100K miles in the case of Hyundai / Kia) is only a good match / selling point for a buyer who does not intend to keep the vehicle much past the warrantee period . At 48K miles my Hyundai magnetic drain plug had approx. a 1/2" of metallic crude on it (pretty routine I suppose) and the ATF while mostly red in color had some brown color creeping into it and was faintly starting to smell burnt. Again , I'd say not bad and I suppose fairly routine for the mixed driving in Georgia (especially the summers here) . Conversely , the thought of not doing a ATF drain & fill until 100K miles (or even 60K miles) would make me cringe ... I suppose I am in the minority here .
It's your car, change it as often or as little as you want. It has a drain plug and H/K give a service interval, so why confuse things with references to "sealed transmission" ? I think changing it every 25k is pretty overkill considering H/K says for severe service to do it at 60k.
I agree, if you didn't like how it looked after 48K mi. then change it more often than that. I'd change it again around 30K mi and if it looks like it didn't need it, wait longer next time.

I do think 30K is probably overkill, but it's only 6 years old so not really enough data as they age to know if they're going to succumb to premature tranny failures over the longer term, and your time (assuming DIY) and the fluid may be a lot cheaper than transmission work.

It is probable that your instinct to change around 50K mi (including next time) is about right. They likely decided that the initial fill will make it to the warranty period then why risk an owner or shop messing something up to change it before then as it can be more likely to cost Hyundai than benefit them. I realize this seems contradictory to what I previously wrote, just depends on how much work to put into trying to eek out a little longer life... then some texting teenager t-bones you and totals it and none of that mattered. ;)
I bought mine used at 84k miles (2.4L, 6 speed, 2016MY) and got three D/F’s done over 5k miles. (first two done around 85k with the last being around 90k)

Just did another D/F at 119k, I’ve been throwing towing, sand driving, etc at it with elevated temps (230 F) in the case of the latter but it seems to be content so far.

I didn’t own the car then - and it’s possible it was done, but I’d prefer to get the first ATF change probably around that 50-60k mark if I was owning it by then.
At 50k I had the coolant changed and the transmission fluid in wife's 17 Tucson. This was the 6 year mark, it was due for it. I'll probably do it again at 100k.
At under 40k miles I recall the factory ATF being nearly dark as used engine oil on my 2008 Hyundai Santa Fe with the 2.7l V6 and 4spd AT. That one has a drain plug and a dipstick for the AT. Good ol days.