History: 2019 Grand Caravan bought new March 2020. December 2020 deer strike...radiator replaced with LKQ during repair. October 2021, developed small leak near top 2-inch hose....not actually visible, but pink antifreeze stain pattern showing as a spray from slightly below this 2-inch hose. When I drained the coolant out for radiator replacement, the reservoir tank easily sucked dry during the draining, so I am convinced there is no pinhole leak in this reservoir hose. Radiator replaced with new. Radiator cap replaced with new OEM 16psi. August 2023 small leak appeared to be at same area...not visible, but same spray pattern of pink staining....Now whole system flushed with distilled water 4 times, until water drained out is clear. New radiator again, new 50-50 mix, allowing for distilled water still in system....Now the question: Why is the amount in the overflow / reservoir tank never changing. I marked it and monitor it hot vs cold. Not a bit of movement. Opening the radiator cap when cold shows fluid is to the top as normal. What am I missing? I suspect the system was building too much pressure, causing the radiator to generate a pin-hole leak, spraying the coolant out....ideas??.

 

I am having a similar issue. Coolant from the reservoir is not going back to the engine.

 

I would venture to guess that it is changing, but changing so little that it goes unnoticed.