Normally you will get a lot of good info from this forum.
Not so much this time. Brown muck in the
oil is generally caused by a faulty gasket or cracked block.
(water leaking into the
oil) And 120 degrees Celsius is NOT optimum
oil temp.
Your oil temp is fine. If it drops to around 90 at freeway speeds on that 80 degree day then you are golden. By the way, your oil temp is measured at the remote oil filter prior to it flowing through the oil cooler.
You're fine, enjoy the ride.