A viewer asked why aren't the oil pumps in turbine engines just routinely replaced after a specified interval of running. For a variety of reasons, things in the aviation world are a bit different from the way cars are maintained.

Links:
The video which sparked the question...
Oil Pump Rebuilding and Testing :    • Jet Engine Oil Pumps:  Rebuilding and...  

Jet Engine Lube Pump Overhaul:    • Jet Engine Lube Pump Overhaul  

Jet Engine Lube System:    • Jet Engine Lube System