Engines & Transmissions Sticky Index (look here for good info)

[Eggman]

Any recommendations on an additional transmission fluid cooler I can get installed and working in conjunction with its original? 2015 Mirage CVT

The Jatco JF015E (CVT-7) CVT used in the Mirage has a heat exchanger that is mounted within the transmission housing and is tied in with the engine coolant/antifreeze circuit. Just as an internal-combustion engine is most efficient when it is at it's full operating temperature, so is the CVT.

I would advise against spending money on a transmission cooler as it's temperature is intended to be maintained with the engine. Instead consider using the money and effort in a transmission fluid replacement and filter change.