In the past 10 years I received numerous calls questioning the Generator powered booms vs. the PTO powered booms.
I have found that the Onan Generators are very reliable and much more cost effective as there counterpart the PTO powered booms.
Most of the PTO powered bucket trucks or boom trucks are diesels. Lets say we have a 2005 Ford Diesel (and lets pretend that 6.0 Diesel motor is still running) now the odometer reads 120,000 miles. That is NOT a true 120K. That particular truck has been idling everyday it has been on the job site for as many hours it was in use on the job site. For example that truck is 10 years old. In order to get the correct wear and tear on the engine you must multiply the hours in service times the days in service to get the idling hours for that particular engine. As you can see a 10 year old truck has much more wear and tear than the odometer reading.
Most mechanics will tell you not only do you have the extra idling hours but you also have idling which is one of the worst things you can do to that engine.
Now the Onan Generators are the main power source for the bucket trucks. You turn off the trucks engine when at the job site site start the Onan use less fuel and save the trucks engine.