Q&A

I don't know what the hissing noise is, you'll have to get down on it and ID it by listening. The operational pressure if the A/C system is more like 150 PSI on the high pressure line and about 40 PSI on the low side line. Get the system checked by a Dodge specialist and get a diagnosis.
I don't know how you measured the pressure but you have two pressures to consider, not just one and a figure is meaningless if you don't tell me where in the system you measured it.
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https://repairpal.com/directory?address=55378&car_bra...