How is the trans fluid level?
When was it's last change?

I'm not a real believer in fluid flushes on higher mileage bits, but a couple changes over a few weeks will replace most of it through dilution. Even a single change may help things out.
Fairly cheap and easy to do.

 

I checked that before getting the issue fixed the first time. The fluid is good. Any other ideas?

 

Assuming there's nothing mechanically wrong with it, you could try resetting and relearning the adaptive values. You will need either a high-end diagnostic tool or a cheap USB adapter and Cascade. Then follow this TSB...

http://www.revbase.com/BBBMotor/TSb/DownloadPdf?id=166399

That Cascade thread can be a little overwhelming, but you don't need to modify the adapter for doing this.

 

BTW, where are you located? Someone from this forum may be near you and have Cascade.

 

Boulder, CO. Should I just go to the Hyundai dealership and show them this?

 

I'm really good with computer software and learning stuff. I just checked that thread you linked about cascade but the dl link is down. any help?

 

How many miles on your car? May be it's just time for it to break

 

hello im new and have this issue also on my 06 tibby T with auto and v6 engine 106,000k on it. i was just told by a former tibby owner that remove the battery overnight and in the morning connect the battery and drive it normal for couple hundred k and it should relearn shift points, i will try and let you know.

 

Let me know your results. I am also having the same issue, but mine happened/got worse after I got a dead battery. Perhaps I just drove it too aggressively-combination of ignorance and bad luck. My dealer said they want $150 to flash the TCM, so I'm going to look a bit wider for pricing on the TCM flash too.

 

Have you checked your transmission/motor mounts?
also, I had this exact problem and it shifted *violently* until it shifted extra poorly one day and threw a check engine light. I replaced the transmission speed sensor and my front and rear motor mounts. Fixed all the problems. i had a hose dripping coolant for a while and i guess that shorted out one sensor, but i replaced both. The sensors cost me like $25

 

Have you checked your transmission/motor mounts?
also, I had this exact problem and it shifted violently until it shifted extra poorly one day and threw a check engine light. I replaced the transmission speed sensor and my front and rear motor mounts. Fixed all the problems. i had a hose dripping coolant for a while and i guess that shorted out one sensor, but i replaced both. The sensors cost me like $25

where did you get the sensors? This issue just happened Right now to my boyfriend And he has coolant leaking and we were going down a highway and it shifted hard and threw the check engine light, got a diagnostic and it threw The code P0700

 

Update: Got my car back from the shop yesterday. They flashed the TCM and changed my SP III. Seems to be shifting way smoother. I'm still going to be torquing the engine mounts again but just got to reading that in the service manual. It may be a day or 2 before it gets warm enough again to encourage me to do it (mid 20s right now).

Random question for a mechanic: Could a suspension issue feed back into the transmission to cause more load/wear on the trans?

 

Did this seem to fix your issue? My Tib runs perfectly other than that 2nd to 3rd hard shift, and I have been holding off on mods until I get the issue resolved.