# Engine coolant type and antifreeze mixture (NB2)

Canonical URL: https://miatatorque.com/spec/coolant-type-and-mixture-nb2/

Applicability: NB 2001–2005 (BP-Z3) — Other years in this family inferred from 2005 factory evidence with owner approval; actual-year verification is separate.; NB 2004–2005 (BP-Z3-TURBO, 6MT) — Common coolant type and mixture from the generic 2004/2005 replacement procedure; capacities remain variant-specific.

Confidence: fsm

Ethylene glycol-based coolant mixed with soft (demineralized) water; By volume: 35% coolant / 65% water for protection above −16°C (3°F); 45% / 55% above −26°C (−15°F); 55% / 45% above −40°C (−40°F). Do not use alcohol- or methanol-based coolant.

Always confirm against your factory manual. Match every restriction and follow all stages and procedure notes. Disputed claims must not be automatically resolved. The complete record below preserves every printed unit, source claim and procedure.

```json
{
  "id": "coolant-type-and-mixture-nb2",
  "name": "Engine coolant type and antifreeze mixture (NB2)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NB",
      "years": [
        2001,
        2005
      ],
      "engines": [
        "BP-Z3"
      ],
      "note": "Other years in this family inferred from 2005 factory evidence with owner approval; actual-year verification is separate."
    },
    {
      "gen": "NB",
      "years": [
        2004,
        2005
      ],
      "engines": [
        "BP-Z3-TURBO"
      ],
      "trans": [
        "6MT"
      ],
      "note": "Common coolant type and mixture from the generic 2004/2005 replacement procedure; capacities remain variant-specific."
    }
  ],
  "kind": "fluid",
  "fluid": {
    "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water",
    "notes": "By volume: 35% coolant / 65% water for protection above −16°C (3°F); 45% / 55% above −26°C (−15°F); 55% / 45% above −40°C (−40°F). Do not use alcohol- or methanol-based coolant."
  },
  "procedure": {
    "notes": "Ratios are by volume and depend on required freeze protection. Do not use alcohol or methanol. Follow the cited year-specific filling, bleeding and level-check procedure; never open the cooling system hot. Specific-gravity figures differ in the 2005 table and are not combined into a universal target."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-2003",
      "page": "PDF p. 643",
      "as_printed": "Use only ethylene-glycol-based coolant.\nUse only soft (demineralized) water in the coolant mixture.",
      "verified_years": [
        2003,
        2003
      ],
      "fluid": {
        "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water"
      },
      "document": {
        "id": "fsm-2003",
        "tier": 1,
        "title": "2003 Mazda MX-5 Miata Workshop Manual (electronic manual capture)",
        "covers": [
          {
            "gen": "NB",
            "years": [
              2003,
              2003
            ],
            "engines": [
              "BP-Z3"
            ]
          }
        ],
        "note": "Normally aspirated BP procedures audited; turbo procedures are covered separately."
      }
    },
    {
      "source": "fsm-2003",
      "page": "PDF p. 644",
      "as_printed": "Antifreeze solution mixture percentage\nCoolant protection\nVolume percentage\nWater\nCoolant\nGravity at 20°C {68°F}\nAbove −16°C {3°F} 65 35 1.054\nAbove −26°C {−15°F} 55 45 1.066\nAbove −40°C {−40°F} 45 55 1.078",
      "verified_years": [
        2003,
        2003
      ],
      "fluid": {
        "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water",
        "notes": "By volume: 35% coolant / 65% water for protection above −16°C (3°F); 45% / 55% above −26°C (−15°F); 55% / 45% above −40°C (−40°F). Do not use alcohol- or methanol-based coolant."
      },
      "document": {
        "id": "fsm-2003",
        "tier": 1,
        "title": "2003 Mazda MX-5 Miata Workshop Manual (electronic manual capture)",
        "covers": [
          {
            "gen": "NB",
            "years": [
              2003,
              2003
            ],
            "engines": [
              "BP-Z3"
            ]
          }
        ],
        "note": "Normally aspirated BP procedures audited; turbo procedures are covered separately."
      }
    },
    {
      "source": "fsm-2004",
      "page": "PDF p. 675",
      "as_printed": "Use only ethylene-glycol-based coolant.\nUse only soft (demineralized) water in the coolant mixture.",
      "verified_years": [
        2004,
        2004
      ],
      "fluid": {
        "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water"
      },
      "document": {
        "id": "fsm-2004",
        "tier": 1,
        "title": "2004 Mazda MX-5 Miata Workshop Manual (electronic manual capture)",
        "covers": [
          {
            "gen": "NB",
            "years": [
              2004,
              2004
            ],
            "engines": [
              "BP-Z3"
            ]
          }
        ],
        "note": "Normally aspirated BP procedures audited; turbo procedures are covered separately."
      }
    },
    {
      "source": "fsm-2004",
      "page": "PDF p. 676",
      "as_printed": "Antifreeze solution mixture percentage\nCoolant protection\nVolume percentage\nWater\nCoolant\nGravity at 20°C {68°F}\nAbove −16°C {3°F} 65 35 1.054\nAbove −26°C {−15°F} 55 45 1.066\nAbove −40°C {−40°F} 45 55 1.078",
      "verified_years": [
        2004,
        2004
      ],
      "fluid": {
        "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water",
        "notes": "By volume: 35% coolant / 65% water for protection above −16°C (3°F); 45% / 55% above −26°C (−15°F); 55% / 45% above −40°C (−40°F). Do not use alcohol- or methanol-based coolant."
      },
      "document": {
        "id": "fsm-2004",
        "tier": 1,
        "title": "2004 Mazda MX-5 Miata Workshop Manual (electronic manual capture)",
        "covers": [
          {
            "gen": "NB",
            "years": [
              2004,
              2004
            ],
            "engines": [
              "BP-Z3"
            ]
          }
        ],
        "note": "Normally aspirated BP procedures audited; turbo procedures are covered separately."
      }
    },
    {
      "source": "fsm-2005",
      "page": "PDF p. 733",
      "as_printed": "Use only ethylene-glycol-based coolant.\nUse only soft (demineralized) water in the coolant mixture.",
      "verified_years": [
        2005,
        2005
      ],
      "fluid": {
        "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water"
      },
      "document": {
        "id": "fsm-2005",
        "tier": 1,
        "title": "2005 Mazda MX-5 Miata Workshop Manual (electronic manual capture)",
        "covers": [
          {
            "gen": "NB",
            "years": [
              2005,
              2005
            ],
            "engines": [
              "BP-Z3"
            ]
          },
          {
            "gen": "NB",
            "years": [
              2005,
              2005
            ],
            "engines": [
              "BP-Z3-TURBO"
            ],
            "trans": [
              "6MT"
            ]
          }
        ]
      }
    },
    {
      "source": "fsm-2005",
      "page": "PDF p. 734",
      "as_printed": "Antifreeze solution mixture percentage\nCoolant protection\nVolume percentage\nWater\nCoolant\nGravity at 20°C {68°F}\nAbove −16°C {3°F} 65 35 1.057\nAbove −26°C {−15°F} 55 45 1.072\nAbove −40°C {−40°F} 45 55 1.086",
      "verified_years": [
        2005,
        2005
      ],
      "fluid": {
        "type": "Ethylene glycol-based coolant mixed with soft (demineralized) water",
        "notes": "By volume: 35% coolant / 65% water for protection above −16°C (3°F); 45% / 55% above −26°C (−15°F); 55% / 45% above −40°C (−40°F). Do not use alcohol- or methanol-based coolant."
      },
      "document": {
        "id": "fsm-2005",
        "tier": 1,
        "title": "2005 Mazda MX-5 Miata Workshop Manual (electronic manual capture)",
        "covers": [
          {
            "gen": "NB",
            "years": [
              2005,
              2005
            ],
            "engines": [
              "BP-Z3"
            ]
          },
          {
            "gen": "NB",
            "years": [
              2005,
              2005
            ],
            "engines": [
              "BP-Z3-TURBO"
            ],
            "trans": [
              "6MT"
            ]
          }
        ]
      }
    }
  ],
  "jobs": [],
  "system": "cooling",
  "component": "gap-followup-2026-10",
  "componentName": "Additional factory manual gap audit",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/coolant-type-and-mixture-nb2/"
}
```