Thank you very much for your suggestions!
I'm living in sweden and it's still pretty chilly here despite summer coming. And gauge gets a little bit higher when i press it on the motorway so i believe it's not the termostat (>200$ new!!!). Also, when a drive for a few minutes pipes going to front oilcooler are still cold, which implies that termostat hasn't opened and is working properly. Probably just gauge being old & worn
Now if i just could find out where the funny screeching sound from a back is comming from (it's following wheel rotation, but it's not rumbling)...hopefully not the wheel bearing
((