Everyone will tell you a thousand different things. Asking what brand of oil or asking what type of lift to install will get all sorts of folks barkin' about whats best for ya.
I won't tell you whats best. But I'll tell you what I run in my 94' 4.0 w/about 180,000 on it. I run Quaker State or Castrol GTX 5w-20. The 5-20 is a thinner oil and seems to lubricate to the top end much faster and keep my lifter ticking a lot quieter. I started going to thinner oil after realizing that anytime I put in a 10-40 or Lucas that my lifters ticked almost twice as loud as they do once the oil is thinned out.
Been runnin' 5w-20 year around w/no issues, no burning oil, no over heating and very minimul ticking from the top end. I'd say from experience, go thinner not thicker. But no matter what, figure out whats best for your engine. If you try a new oil, pay attention to the sound of it at idle at up through the gears once changed. Then, run it a couple weeks and see how it sounds. If you don't like it, change it to something else and re-compare how it runs. Should stay quiet and cool, thats what we want.