Re: 4.0 sohc oil pan
If rod bearings NEED replaced, most likely your crankshaft is going to need professional machine work.
I have only replaced rod and mains in an engine with out machine work (180K), under these conditions - they weren't causing any problems and the bottom end was fine. Crank looked really good and no gouges that caught my finger nail across the journal. I did it because I had the pan off for a rear main seal replacement, so I replaced bearings, timing chain, oil pump/pickup. I have a spare engine for the car, so it isn't a huge deal if it fails (which has been doing fine so far).
If you put good bearings, on a bad crank journal, be prepared to find another engine, because it will fail. Old boss did this on a 3.0L Vulcan, engine lasted 2 days at best.
1987 Ford Ranger Short Bed 5.0L/T-5 Project
1988 Ford Ranger Long Bed Parts Truck
1993 Ford Tempo 2.3L OHV HSC Auto - D/D Stock.
1999 Honda Accord VTEC Auto
2002 Dodge Caravan - 3.3L Auto