[Phil №❶]

Greetings Mountainlady,

Thanks for coming back. The auto trans is a myriad of valves, clutches & gears. Controlled by many outside factors, (throttle position, load etc) it's full of valves that can fail but reliability is normally pretty good. I have had 0 problems with our 2 vehicles and when operating correctly, they are a delight to drive. Hope your trans is sorted soon. 

[komaterpillar]

just read this whole thread for the first time.

sounds to me like the lock-up clutch in the convertor or the spool that controls it is the cause of the dramas.

has anyone having problems with a diesel auto had the engine stall when coming to a stop after driving above 45-50 klm/hr? if so this is a symptom of the lock-up clutch not releasing and stalling the engine and this would be accompanied with the symptoms previously described ie. jerky operation in 3rd and 4th, won't kick down from 4th to 3rd or is very harsh but is fine when done manually.

the reason it is smooth when done manually is when you move the gear selector from 4th to 3rd the ecu disengages the lock-up clutch regardless, rather than try and workout wether or not to leave it locked or unlocked.
the lock-up clutch only operates in 3rd and 4th to so that is why most of the problems will be only in these gears.

my 2 cents worth 

[Phil №❶]

I think that info was worth more than 2 cents, thanks kom. 

[Hornet]

Has the new valve been fitted in the transmission yet and if so how did it go. I appear to have the same problem in my 2011 CRDI that is coming up for the 15,000k service. At the 7,500k service I mentioned this problem and was told  by the dealer nothing was wrong a computer test said gearbox OK. I will be asking for it to be rectified this time.

[Talking Hoarse]

Has the new valve been fitted in the transmission yet and if so how did it go. I appear to have the same problem in my 2011 CRDI that is coming up for the 15,000k service. At the 7,500k service I mentioned this problem and was told  by the dealer nothing was wrong a computer test said gearbox OK. I will be asking for it to be rectified this time.

Good morning Hornet.
This thread has been running a while.  Might be best if you describe your own (cars) symptoms?
My own 2010 CRDi auto did have a violent judder when trying or refusing to kick down to 3rd at about 50mph /1500rpm.  This was resolved by a new auto gearbox.  However my car has also sometimes suffered uneven running at about 1500rpm usually about 5 minutes after startup - this was resolved with a tank full of Shell Vpower diesel, and subsequently an occasional small dosing of injector cleaner (eg RedEx).
Plesae let us know how you get on.
Long live Hyundai's 5-year warranty.
Ed