Suzuki: engine oil, professional mechanic, suzuki vitara

Question
what oil do i need to put in my 1991 suzuki vitara? its carby 4 cylinder. eg. syntetic, semi syntetic etc?

Answer
Stay with the viscosity recommendations in the manual, which is usually 5w-30.  Whether synthetic, blend, or not is up to you.  You get what you pay for, thus, full synthetic is best, and so on with descending price.  As a 35 year professional mechanic, I cannot strongly enough suggest that you change the oil and filter at least twice as often as the factory manual requires.  I personally use full synthetic in my 87 Samurai.
scotty