Just bought a 1987 300zx turbo and put 5w30 in it. With winter coming up here i figured that was a good choice and was wondering what you guys use? i use castrol 5w30 most of the time. I was also wondering how well Slick 50 works? i guess it seals up any leaks? and one more quick thing, i cant find where to put the tranny fluid in, I looked by the firewall and didnt see it so any help would be greatly appreciated.