After fininishing the rinse phase in the wifes 97 Jetta need to decide which way to go. Its seen nothing but 30W's even GC. For some reason its always had a lifter tick. Now that im using Valvoline 10W40 its pretty much went away. Mind you i did a previous clean and rinse phase about a year ago. Since then ive been doing mainteice doses...all with 30W's.