Congrats on the new ride. First job is to find a good independent mechanic. Freightliner and the brand name shops cost an arm and a leg per hour and you never know who is going to work on your rig.
Hopefully you got service records. Most DPs require a full fluid change every 5 years. Differential, power steering, coolant flush and replace (use extended life)new thermostat, trans, air system dessicant, fuel and oil filters. Same for genset. I would do belts and hoses as well.
If you didnt get any records, I would want to establish a baseline.
Hopefully the tires are fresh.
