Southern Pacific: Oil firing-only steamers?

[Lone Cat]

I've heard that Southern Pacific steam locomtives are all oil-fired. and Espee did this before they introduced cab forwards.
1. When was the first time SP introduced oil-firing steam locomotives?
2. Why? they did oilfirings BEFORE the cab forwards concept was even enters the train engineers thinking. Do they believe that marine fuel oil is the best fuels in the world? isn't there any coal mines there?
3. When was the first time they buy diesel locos?
4. Do they ever consider electrify one of their rail lines? if not? why?
5. Why SP scrapped all cab forward steamers? (except the 4929). did they join G.E. Dieselization programs? (which one part of the deal required a railroad company to scrap its very own steamers)

[thietavu]

I suppose oil burning somewhat lowers the maintenance costs of steam engines (correct me if I'm wrong) - and the price of oil has been low in the USA compared to e.g. Europe. Just check the prices of gasoline even today... As for scrapping about all the steam engines, that seems to have happened everywhere in the world. One very nasty example: here in Finland a one-of-a-kind spare boiler was destroyed in a hurry some years ago just to prevent it from getting installed into one steam engine about to become restored. Some people simply act like that. Some maybe for money, but some simply because they can.