Originally Posted by MSRP.

Probably not a popular view, but does the "leak" stablilize at a specific level?
Bought my 03' v8 with 155k miles (~250k km) that I also thought had a "leak".

Picking up, it was just a CM or so below the "low" mark. Filled with Toyota LL coolant, and on the 6 hour drive back home, it had returned to the same mark.
No obvious signs of leak, it is SOMEWHERE, maybe a cracked rad?.. but it stays there on the money.

Changed timing belt/WP and issue is the same, top it up, drops back to that identical level.
FWIW, I have just ignored it. Driven an additional 70,000km since without skipping a beat, including high speed runs to Florida through the mountain passes of north and south Carolina, no overheating, strong as a bull.