U.S. Cash Products-Chicago, Group Three prices up as refinery workers strike

* Gulf gasoline up sharply on key unit outages at regional refineries * NY Harbor gasoline differentials mixed, RBOB weaker * RINs credits prices mixed HOUSTON, Feb 9 (Reuters) - Chicago gasoline and diesel differentialsstrengthened more than a penny on Monday in reaction to an expanded strike byU.S. refinery workers at two refineries in the region, traders and brokers said. Differentials in the neighboring Group Three region in the Midwest alsostrengthened. Chicago CBOB gasoline sellers were asking 4.25 cents under the benchmarkMarch RBOB gasoline futures contract for cycle-2 February barrels, 1.50cents stronger than where it was valued late on Friday. Sellers of ULSD for cycle 2 were asking 7.50 cents under March heating oil, after it traded at 9.00 cents under on Friday. The United Steelworkers union said a strike by U.S. refinery workersexpanded on Sunday to BP Plc's Whiting, Indiana, refinery and thecompany's joint-venture refinery with Husky Energy in Toledo, Ohio. Group Three gasoline strengthened about 0.25 cent to 1.50 cents under theMarch RBOB, while ULSD was pegged a penny stronger at 3.50 cents under Marchheating oil. Some brokers cited stronger gasoline differentials on the U.S. Gulf Coastand refinery work in that region as part of the strength in the Midwest. U.S. Gulf Coast cash gasoline differentials swung to premiums to March RBOBfutures on Monday on news of key gasoline-making unit outages at a pair of majorregional refineries, traders said. Marathon Petroleum Corp shut a fluid catalytic cracking unit (FCCU)and associated alkylation unit at its 530,000 barrels per day (bpd) refinery inGaryville, Louisiana, on Saturday because of unknown mechanical issues, industryinformation firm IIR Energy said on Monday. IIR said the units are expected toresume service this weekend. Exxon Mobil Corp also has shut two FCCUs at its 502,500 bpd refineryin Baton Rouge, Louisiana, for a previously reported 54-day turnaround. A4 CBOB, or conventional regular gasoline blendstock formulated for blendingwith 10 percent ethanol, traded at 2.00-cent and 1.25-cent discounts to MarchRBOB futures and later at a half-cent premium, up 2.75 cents per gallon overall,traders said. Conventional M4 gasoline traded at 0.75-cent and half-cent discounts andthen an 0.75-cent premium to futures, also up 2.75 cents per gallon, traderssaid. New York Harbor differentials were mixed. M4 conventional gasoline was uphalf a cent at 1.50 cents under March RBOB futures. F5 RBOB slipped 1.50 centsto 6.25 cents under March RBOB for barrels by Feb. 10. ULSD strengthened 0.75 cent to 2.25 cents over March heating oil, while highsulfur heating oil slipped half a penny to 6.00 cent under. Renewable Identification Number (RIN) credits were mixed, traders andbrokers said. Ethanol RINs for 2015 compliance year traded from 73 and 73.5cents each, after trading on Friday at 73 cents. Credits for 2014 traded at 74cents, maintaining the recent 0.50- to 0.75-cent premium to 2015 credits,brokers said. Biodiesel credits for 2015 traded a penny weaker at 90 cents. Credits for2014 were pegged at a bid-ask spread of 74/77 cents, weaker from Friday's spreadpegged at 76.5/78 cents. For more refinery news, please go to Latest day Timing NYMEX Bid Offer Change Contract U.S. GULF COAST <0#P-USG> * Scheduling A4 CBOB gasoline Cycle 10 RBOB 0.25 0.75 2.75 M4 conventional gasoline Cycle 10 RBOB 0.50 1.00 2.75 62-grade ULSD Cycle 9 HO -5.50 -5.00 -0.50 54-grade jet fuel * Cycle 9 HO -12.50 -11.50 -0.50 Heating oil * Cycle 7 HO -16.00 -15.00 -0.75 NEW YORK HARBOR <0#P-NYH> M4 conventional gasoline Prompt RBOB -1.75 -1.25 0.50 Any-Month RBOB -1.00 -0.75 0.75 F5 RBOB Prompt RBOB -6.50 -6.00 -1.50 Any-Month RBOB -4.75 -4.25 -1.50 ULSD Prompt HO 2.00 2.25 0.75 Any-Month HO 1.75 2.00 0.50 Heating oil Prompt HO -6.25 -5.75 -0.50 Any-Month HO -6.25 -5.75 0.00 Jet fuel Prompt HO -6.00 -5.50 -0.25 Any-Month HO -6.25 -5.75 -0.25 MIDWEST <0#P-G3> <0#P-MC> Chicago CBOB gasoline Cycle 2 RBOB -5.25 -4.25 1.50 Chicago ULSD Cycle 2 HO -8.50 -7.50 1.50 Group Three gasoline RBOB -1.75 -1.25 0.25 Group Three ULSD HO -3.75 -3.25 1.00 (Reporting by Kristen Hays in Houston and Robert Gibbons in New York; Editingby Cynthia Osterman)