Right amount of coolant??

Discussion in 'Gen 4 Prius Care, Maintenance and Troubleshooting' started by priusrust, Mar 10, 2026 at 1:51 PM.

  1. priusrust

    priusrust Member

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    went to Toyota parts....asked how much anti-freeze coolant my 2016 takes.
    Parts guy looked it up and said 13 quarts ......

    Then looked up cooling system in my owners manual, and it tells me for capacity: 6.2 quarts (gasoline engine) and 1.5 quarts (power control unit).

    I'm confused.....I want to drain coolant and fill up with new coolant. Simple.
    I asked them about discrepancy and they and they honestly were mystified....not slightly off...it's double!
    Help appreciated, thanks!
     
    #1 priusrust, Mar 10, 2026 at 1:51 PM
  2. rjparker

    rjparker Tu Humilde Sirviente

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    Generally you only get half out on a drain and fill.
     
    #2 rjparker, Mar 10, 2026 at 1:52 PM
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  3. Mendel Leisk

    Mendel Leisk MMX GEN III

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    I think it's mechanically similar to gen 3, at least for coolant volumes. From my notes when I changed both circuits:

    engine coolant drain: 4.25 liters roughly
    inverter coolant drain: 1.5 liter roughly
     
    #3 Mendel Leisk, Mar 10, 2026 at 2:42 PM
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