Normal Oil temperature

[Koen]

hello everybody!

I am driving my volvo 740 with a d24tic for about a year now and noticed that the there is something wrong with the oil. It has a air/oil-cooler.
After a couple of oil changes, 2 broken turbo's and a cracked head, i bought a oil temp gauge to be able to keep an eye on the temperature.

After a 15 minute drive at a constant 130km/h (65miles/hour) my oil goes all the way up to 125°C (257°F). At this point i drove off the highway so i don't know if it would have gone higher. It was 20°C (68°F) outside and i started the highway drive at 70°C (158°F) oil temp.

When i took the air/oil cooler apart i noticed nothing strange about it, it's not blocked or anything. I already tried a different oil thermostat and thermostat housing, doesn't change anything.

So my question is:
Does anybody have a oil temp gauge, so i can compare values?
Is there something about my oil cooler that i didn't check and could be the problem?