Hello, I always put Rotela Triple action 15w40 in my 350 gas engine boat. it seems that Rotela changed their formula with T4 instead of Triple Action. Triple action has these API : API: CJ-4, CI-4 Plus, CI-4, CH-4, CG-4, CF-4, CF. · API: SM, SL, SJ, SH · ACEA: E9, E7 · etc... We can see API : SM , for gasoline engine. Now T4 has these API :15W-40 CK-4, CJ-4, CI-4 Plus, CI-4, CH-4; ACEA E9; JASO DH-2, MA, MA2; Caterpillar ECF-2, ECF-3; Cummins CES 20086, 81; Detroit Fluids Specification (DFS) 93K222, 93K218; Deutz DQC III-10 LA; MACK EO-S 4.5, EO-O Premium Plus; MAN M3575; MB-Approval 228.31; MTU Category 2.1; Allison TES-439; Volvo VDS-4.5, VDS-4 no more API SM !! Is there a reason ?