DD15 fan hub kick in temp

I have a 2017 freightliner with a DD15, I was wondering if you can adjust the fan kick in temp a bit lower?

My fan comes on at 105 degrees Celsius and seems to work fine, however I am getting a very small amount of coolant getting pushed through the radiator cap, like 200mls per 5000km of driving.

I have done all the tests and replaced the rad cap but I can't find anything wrong with it, and some times it will go a week or two without doing it.

My only thought is that every now and then when the temp hits 105 the pressure builds just slightly too much and pushes a tiny bit out, if I drop it to 100 maybe it's not pushing the limit.

Truck rarely runs hot, only when u would expect it to, nothing out of the ordinary

Have changed the thermostat as well, so if this doesn't work I will just live with it and top up coolant every month.