Looks like a nice engine that they put together. Again it is your choice. I see this company recommends Shell Rotella 15/40 for their engines. Rotella is said to be the best 15/40 oil out there. I have sold plenty over the years.
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1967 Marlboro Maroon 4spd Coupe 1973 Dark Blue 4spd Coupe w/air, original 25,000 miles 1999 Black C-5 Hatchback Coupe 6spd LS1 1934 Ford 3 Window Coupe eng. code "ZZZ" 350-345hp Chevy Powered! 1970 Black on Black Monte Carlo(FOR SALE)Asking $18k