fmugur, teknik_ranger, FYI, I tested my transmission last year going to work (50km) and got lower temperatures than fmugur's.
Mine is a 6spd though, so may be that is the reason for the difference.

I tested it with Inpa and got a stable reading of 86°C (187°F) after driving 40 minutes. I tested it in summer and winter and got the same readings.

I did the same test this summer towing my racecar on highway with several uphills, but I can't find the data right now. If I find it, I will edit this post.

Thanks TB, If I didn't hook up the oil lines backwords than I will have to insert a tranny cooler as civdiv did.
I need somebody to clarify the inlet/outlet. The heat exchange thermostat is brand new as well.

TB, what was your engine temperature then? I think yours should be somewhere close to what I got. I know 108 C is the optimal running temp for my 4.4 engine.

well, as long you know the direction of flow, you know which is hotter than the other, cause the trans fluid leaving the cooler suppose to be @coolant temp (or cooler than the other line).

I wonder if replacing radiator will actually doing what bigger trans cooler will do (oxidized alum as well as crud build-up inside the radiator logically conducts less heat transfer, just a thought).

The heat exchanger controlls the tranny's temp and I guess I can figure it out which line is in and which one is return. The outer temperature from the heat Exchanger should be warmer when the engine/tranny are cold but after that it's hard to tell just a few degrees. It does matter how I connect the lines to the heat exchanger for efficiency but really that much?
I am thinking that the problem might be the heat exchanger itself. Clogged maybe? Lost efficiency?

There are aftermarket heat exchangers available which look similar to the original .
I found some biofuel heaters which may be an easy fit in a sort of piggy back fitment with the original .
Best do your own research as to suitability .

HEAT EXCHANGER biofuel veg vegetable cooking oil SVO | eBay

I will stay with OEM just to avoid custom connections but I wonder why the heat exchanger does not do a good job anymore to keep the temperature to the coolant temperature.
I am thinking of taking it out and inspect it or buy a new one but the external cooler would do the cooling anyway.

I installed mine as civdiv. The temperature is lower but I have to do some measurements to show the exact difference. It was a challenge to cut the return line and insert the new lines due the inner diameter differences.
An interesting thing when adding oil to the tranny was the temperature measured with IR vs. temperature from inpa. I got about 86 with the Infrared temperature reader and 102 with inpa. I know the temp sensor in the tranny is on the harness which is right at the fill plug lever. I expected the temp to be the same and I wonder why it wasn't. It could be inpa or the sensor in the harness or could be the oil vs. coolant or...
I tried to get the temp from gt1 but I couldn't find it easily. I will try again and compare the readings.

Anyway, so far I am happy with the 2-1 downshift that does not happen or at least it did not happen although I tried hard. Hopefully that was it.

http://i695.photobucket.com/albums/v...-03-21_583.jpg

http://i695.photobucket.com/albums/v...-15-16_697.jpg

Sorry i haven't weighed in; i took a few weeks off and have been bouncing around CO & WY of late.

I used a coupla brass adapters to deal with the transition between the lines. Now, you DID buy transmission cooler hose, and did not use generic fluid or fuel line, correct?

Although you are way up there in metric-land, I assume the temps you indicate are F and not C.

Maybe clean that old radiator and get any gunk or debris outta the fins while yer in there, too.

You scared me now. I used the hose that came in the kit which I thought it was for transmission.
Yes, the temperature was in F.