Just to be safe I'd put some newspaper under it for a day or two and identify exactly where those drips are coming from, including tracing the coolant drip marks back to the source if at all possible. If it's dripping off something and running down your control arms you might start looking in the wrong place.
As for the heat/cool thing, are you sure it's not just that it's after it sits for a while that the drip is noticable? And when things heat and cool, things expand and contract, so keep that in mind.
When you think about it, there are really only going to be a couple places it's leaking. Hoses, water pump, leaky radiator, gasket, anything to do with the heater (if the drips are obviously in the engine compartment then it's only hoses.) Is your radiator plastic or metal? I've read several places that metal radiators are a worthwhile upgrade when the plastic ones start to leak.
97 TJ 6cyl, 5speed 37" Krawlers on American Racing 17" wheels. (Beadlocks someday)
RE 5.5 Long arm, Currie 9" front and rear with ARB's, Warn hubs and axle shafts, CTM u-joints
Optima Dual Batteries, OR Fab roll cage, custom rock sliders, SMF shorty bumpers front and rear.
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