Diesels need to be worked harder than gas engines on break in. Mow some normal thickness grass for a couple hours, use a back or box blade, do some FEL work. Full throttle is ok, but full load is not ok. That means don't do stuff like pull a 2 bottom plow thru hard pack.
Just watch the temps, keep the screens clean and fluids full. Operate for 1 hour - check stuff (visual inspect for bad stuff happening). Operate for 2-3 hours - check stuff. Let it cool - have a lunch break or an adult beverage. Check wheel torques, FEL frame bolt torques, tire pressures, fluid levels, cleen screens and go back to work.
If you baby a new diesel, you are more likely to harm it than operating it at 70-80% of max load. I like to change engine oil at 10 hours on a new or rebuild.
jb