Based on the intake casting number I was able to ascertain the motor I have in my FJ40 is a Buick V6 - 3.8L 231 (1976 I'm assuming). I've been able to nail down most of what I need for a tune up and oil change, but wanted some opinions from those in the know regarding what type of oil to use and am hoping someone knows how many quarts are required. I'm thinking of using Castrol Syntec 10W-30. Thoughts? Opinions?