In my 98 XJ I ran mostly white bottle and green bottle castrol, 10/40 summer and 10/30 winter. Oil change intervals were anywhere between 5-15,000 miles. Ran the big ford style filter in either wix or fram.
I got the jeep with 209k on it and it has 453k on it now. Never been apart, never used more than a quart in 5,000 miles, mostly leaking. I would still be driving it if it wasn’t totally rotted out.
I probably will throw the engine in a wrangler just to see how many more miles I can put on it. It’s on its third clutch in need of its fourth. Clutch was put in at 214k. I hate to toss that motor just because it has been so faithful.