702Rubi

Two different dealers have pressure tested mine. At least according to the paperwork and what they told me. But of course, I have no idea what temperature the engine was at when they did that.

You would think it's obvious they should completely warm it up, maybe take it for a highway spin for a while, and then come back and hook it up. But who knows what they actually did.

Rednroll

Radiator end cap leaks will expose themselves without the engine being warmed up.

LIM gasket, that seemed to be a different case from my experience.

Along with pressure testing the system, what they should be doing is putting dye into the coolant, so they can use a black light to identify where coolant may be leaking from around the engine or other parts of the closed system.

Seizer

I am chiming in late here, but I had slight coolant loss too on my 07 JK. I would just top it off as needed and call it good. What caught my attention was the staining like you showed in your photos. It was along my bell housing (I think that's what it's called/Manual Transmission). I took a mirror and flash light to inspect the rear lower intake manifold area, because the front of the engine was clean as could be. Sure enough I spotted caking and the off color orange that my JK uses. Took it to my shop and told them. They pressure tested it and could not discern an actual leak, even though I had pointed out what I found with my mirror. It wasn't as if it was spraying away, and there were never any fresh fluid drops on the concrete after parking. Since the vehicle has a warranty, I had the shop change the lower intake manifold gasket. Problem solved, coolant level stable, bell housing clean. This is just food for thought. The only reason I thought to check back there was due to another member here having the same leak. This member also did a write up if I recall correctly on how to change that gasket. There's also a youtube video of a guy doing it too. Had this not been covered by my extended warranty I would have done it myself.

It doesn't sound like you have a hellacious leak, but I'd check your oil dipstick. Make sure that there is no sign of coolant in the oil.