My new Volvo 2004 S60 has 1800 miles on it. The filler cap says Volvo recommends Castrol. It's a company car so the oil changes are free, that's the only reason I'm not changing it myself with a quality Synthetic. I decided to go to the dealer for all changes. I called the dealer to inquire what oil they use. They told me they use Citgo Bulk oil. When I told them that the filler cap says Castrol, they said sorry all we use is Citgo Bulk. So much for using the dealer for oil changes. My company will not pay for full Syn so I'm having my normal fleet mechanic use the Castrol Blend. That's got to be better than Citgo Bulk. Does anyone know what the Citgo bulk oil is?