NEW YORK, Sept 19 (Reuters) - It was another day of lossesfor most U.S. cash crude grades on Thursday with refinerymaintenance and a dip in futures prices weighing ondifferentials, traders said.
October Mars sour crude
Mars crude's discount against Light Louisiana Sweet
Gulf Coast sweet and sour crude oil differentials have beenon a steady decline ever since Exxon Mobil Corp beganweeks-long maintenance work at its 503,000 barrel per day (bpd)refinery in Baton Rouge, Louisiana.
U.S. West Texas Intermediate crude
The U.S. front-month contract will expire on Friday.
Planned maintenance work on a 100,000 bpd crude distillationunit at BP Plc's Whiting, Indiana, refinery also weighedon cash WTI differentials.
West Texas Sour
In the futures market, international Brent's premiumover U.S. crude fell to $2.90 a barrel at market close,after both futures contracts fell on Thursday. (Reporting by Selam Gebrekidan; editing by Matthew Lewis)