Transmission fluid change

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88
Location
Charleston, South Carolina
Thread starter
Hello all, 2012 Hyundai Genesis 3.8L 93,8XX miles. I recently purchased the vehicle. I don't think it has ever had transmission fluid service done on it (still trying to verify). I'm wondering, with the mileage of the vehicle, if it would be safe to do a flush or should I stick with a drain and fill. I've heard that doing a flush at higher mileages can lead to the transmission misbehaving. Thanks. Daniel.
 
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110
Location
Tallahassee, FL
If a flush causes any transmission issues, it was living on borrowed time anyways and you lost nothing. Being a reasonably new car and having those miles, I'd not worry about it. Flush it if you want, but a drain and fill with a new filter would be adequate as long as the fluid that comes out isn't too bad. After that, look into a drain and fill every 40-50k.
 
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2,556
Location
Kansas City
IIWM it would get a D&F now and 10K later, then every 20K thereafter. If it is shifting good now the D&F's will be just right IMHO and as always YMMV
 
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24,626
Location
Upstate NY
A drain and fill will "refresh" the ATF. A flush will do a total (almost) fluid exchange. Doing several drain & fills to get to a complete exchange of the ATF is costly and wasteful of ATF. A flush is not really a flush as in some high power machine pushing ATF through the guts of the transmission. Its merely an automated process to allow the pump in the transmission to push new ATF through the transmission. Change filter also if it has one.
 
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88
Location
Charleston, South Carolina
Thread starter
Originally Posted by slacktide_bitog
Just do a drain and fill smile Your Genesis probably has a drain plug. Maxlife is good stuff thumbsup
I'm going to do OEM. Apparently on the 2012s, the 8-speed transmission was a bit finicky so I'm going to play it safe.
 
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1,906
Location
Seattle-ish, WA
What I generally do with a neglected transmission like that is disconnect a cooler line (most cars have them; don't know about that one) and let the fluid collect in a container. Empty the pan, fill it, repeat. Generally this will get 7 to 8 quarts of new fluid into most vehicles, enough to get to 90% new fluid. I agree with Donald that multiple drain/fill is wasteful. If you don't have a cooler line to tap, though, it may be your best bet.
 
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8,301
Location
Virginia
Originally Posted by dan765
Originally Posted by slacktide_bitog
Just do a drain and fill smile Your Genesis probably has a drain plug. Maxlife is good stuff thumbsup
I'm going to do OEM. Apparently on the 2012s, the 8-speed transmission was a bit finicky so I'm going to play it safe.
Nothing wrong with that plan you have.
 
Messages
88
Location
Charleston, South Carolina
Thread starter
Originally Posted by Oro_O
What I generally do with a neglected transmission like that is disconnect a cooler line (most cars have them; don't know about that one) and let the fluid collect in a container. Empty the pan, fill it, repeat. Generally this will get 7 to 8 quarts of new fluid into most vehicles, enough to get to 90% new fluid. I agree with Donald that multiple drain/fill is wasteful. If you don't have a cooler line to tap, though, it may be your best bet.
I think I might do a simple D&F now and another 30k from now, and another 30k after that.
 
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1,906
Location
Seattle-ish, WA
Personally, I'd do two close together, then one every 30k. If you only do one now, you get to about 40% new fluid. If you do two, you get to 64% I looked and it says a 2012 genesis has a ZF 6HP19, 10qts total (maybe the 8spd was an option? probably similar capacity anyway). Assuming a 4qt drain fill, here's your fractional dilution calculations. Looking at the numbers might help you get the picture more easily: https://docs.google.com/spreadsheets/d/1Q09EgQ9YKJf1Q_qROXvstVO4PMeYGlPTXseqFuq3E54/edit#gid=0 However, if you only do a single one now, you are doing a good thing.
 
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