ok I like this response not bad.You don't really need an oil with "extra" zinc. Motor oil formulation has come a long way since the flat tappet days.
Any of the "high mileage" conventional or synthetic motor oils should be fine. Since you like Rotella, there is new version specifically for gasoline engines.
I use Valvoline "Max Life" synthetic blend because it has worked well for me in the past and I have found no reason to change brands just for the sake of change.
ordered valvolineNO, the 4.0L engine's design does not need more zinc than is already present in common good quality engine oils like from Valvoline, Mobil, Castrol, etc.. You need extra zinc for high compression engines with stiff valve springs that cause extra wear on the cam but that's it.
For a high mileage engine like yours Mobil Super 10W-30, a high-mileage design with extra seal conditioning additives, would be very (!) hard to beat.
What keeps our engines running well is nothing more than regular oil and filter changes, not overpriced engine oils like from Amsoil, Royal Purple, etc.
In 50+ years of driving, I have NEVER not once had an engine problem yet I run nothing but conventional engine oils from Valvoline, Mobil, Castrol, etc. And most of my engines were near 200k miles old by the time I get rid of them. My previous TJ had 192k miles on it the last time I saw it, never anything but Valvoline 10W-30 conventional, and its engine was still running like the proverbial top.