Here's my clean 1995 GC limited 4.0 2wd with 270,000 miles.
In about a month I'm driving her from Michigan to Arizona while flat towing my YJ most of the way. I'll be the first to admit that's a pretty tall order for the 4.0 so I'm going to increase the odds of a successful trip.
First step was to test the compression. No point in putting money into a bad engine.
Considering how many miles, the engine tested pretty good.
Dry 110 100 100 95 100 100
Wet 140 120 125 125 140 140
I think cylinders 2,3,4 tested lower because of the head gasket leak.
The zj is in great condition all around with only a few concerns.
Replace Head gasket
Replace Oil pump
While doing that I plan on replacing t stat, valve cover gasket, manifold gasket, injector o rings, and clean the rear diff. Everything else, plugs, wires, cap, rotor, water pump, trans, are all new or in good shape.
On to the fun! Tore everything apart. Head studs where kind of rusty so I let them sit in PB for a few hours. Last thing I need is for bolt to break of in the block.
After a few hours, head bolts came out fine :-)