Golf MkV auto trans overheating?

[metako]

We had our MkV's 09G auto trans fixed a few weeks ago after major slipping when shifting into 4th gear only when warm and ATF reaching 97 deg C (207 deg F) and getting a "17118 gear 4 P0734 003 Incorrect ratio" error message. The Auto trans shop found the N282 K2 clutch control solenoid which controls 4th gear was sticking as well as a few other solenoids, and also the torque converter lock-up clutch control valve was worn/loose in bore and had to be replaced. He checked the valve body bores and they were ok (105,000km on the clock).

The car goes great now and has never shifted so smoothly but just out of interest I attached the vagcom reader and after 35 minutes of lazy suburban driving the ATF temperature is reaching 104 deg C (219 deg F) max. This seems to be a very high reading. Don't know what the max temp was before the repairs as it started slipping badly at 97 deg C and we just stopped the car at that point. The repairer did say the original ATF smelled burned but thought the new torque converter clutch valve would hopefully fix this.

I've read that the 09G TCM has a protective mechanism which kicks in at 127 deg C so maybe any temp below this is ok. Can anyone advise what max temperature they are getting in their 09G trans? I intend to talk to the trans shop soon but would like to be armed with more info before I do. Thanks.

[metako]

Well I've been doing some more reading on the web and looks like 200-220 deg F or 93-104 deg C is about normal. Also the ATF should be the same temperature as the engine coolant as the engine coolant warms/cools the ATF via the little heat exchanger which sits on top of the transmission (visable via the engine compartment). Apparently these can get clogged and stop the engine coolant bringing the ATF temperature down to equal the coolant temperature. This might be happening in our case as the engine coolant temperature was showing half way or 90 deg C when the ATF was showing 104 deg C. See thread and video below:

2009 NB Vert - Transmission(09G) acting erratic 100k miles | NewBeetle.org Forums

VW Transmission cooler Meenan - YouTube

The 09G Design and Function document doesn't specify a "normal" operating temperature only when the protective measures kick in which mainly seems to be locking up the torque converter earlier (see page 47 in the PDF below)

https://www.google.com.au/url?sa=t&r...nIz56mqd_uDL3t

Anyway I'll give the repair shop a call soon and see if he thinks 104 deg C is a problem and maybe look into replacing the heat exchanger. Still be interested if anyone can post up a reading of their own ATF temp.