D dave b Petrolheads Jul 28, 2010 #1 a friend said ha put 15/40 in his 98 sti.is this a good grade and safe to use
R Rob Spec C Octane Boostaholics Jul 28, 2010 #2 10W40 or 15W50 is recommended... I couldn't tell you if 15W40 is alright to use but someone will be able to tell you
10W40 or 15W50 is recommended... I couldn't tell you if 15W40 is alright to use but someone will be able to tell you
