What needs to be done....

Owners Manual should have a list.
What motor?
I have a 2017 DD15 GHG14 motor with 530,000 miles. I had to replace the DPF canisters in May. I had the EGR cooler apart and cleaned with purple power. Cleaned DEF parts with distilled water.

Here is a link to a thread on this site. Many more like it, just use the search top right of this page.

VGT Actuator? | Page 2 | TruckersReport.com Trucking Forum | #1 CDL Truck Driver Message Board (thetruckersreport.com)

 

Somethings I would change/service if they haven't been done-

Drain and flush coolant.

Drain and fill differential

Torque rods

Belts, pulleys, and tensioner.

Air dryer Cartridge and purge valve...

 

Top end adjustment.
The more often the better.