I was just wondering the other day if the valves in the 4.2s have to be adjusted periodically? I have a ticking noise that the truck has had since I got it and am wondering if the valves arent a little bit out of adjustment? If they are adjustable, does anyone have the spec for them? Im putting a turbo on the truck, and it would be much easier to adjust valves BEFORE it goes in lol, so any help is appreciated. Ive heard that the ticking noise might just be normal for the oil pump in these engines.