# Automatic fourth-gear band adjusting locknut (NA 1.8)

Canonical URL: https://miatatorque.com/spec/at-fourth-band-adjusting-locknut-na-bp/

Applicability: NA 1994–1997 (BP, 4AT)

Confidence: fsm

11–28 ft·lb / 15–39 N·m

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": "at-fourth-band-adjusting-locknut-na-bp",
  "name": "Automatic fourth-gear band adjusting locknut (NA 1.8)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NA",
      "years": [
        1994,
        1997
      ],
      "engines": [
        "BP"
      ],
      "trans": [
        "4AT"
      ]
    }
  ],
  "kind": "torque",
  "torque": {
    "nm": [
      15,
      39
    ],
    "kgfm": [
      1.5,
      4
    ],
    "ftlb": [
      11,
      28
    ]
  },
  "procedure": {
    "notes": "On-vehicle adjustment: tighten piston stem to 11.8–14.7 N·m {120–150 kgf·cm, 105–130 in·lbf}, back off two turns, then hold the stem while tightening the locknut. Install a new servo-cover gasket. 1994 factory evidence; applicability to 1995–1997 is inferred within the owner-approved NA 1.8 year group."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-1994",
      "page": "K–78",
      "as_printed": "15–39 N·m {1.5–4.0 kgf·m, 11–28 ft·lbf}",
      "verified_years": [
        1994,
        1994
      ],
      "torque": {
        "nm": [
          15,
          39
        ],
        "kgfm": [
          1.5,
          4
        ],
        "ftlb": [
          11,
          28
        ]
      },
      "document": {
        "id": "fsm-1994",
        "tier": 1,
        "title": "1994 Mazda MX-5 Miata Workshop Manual",
        "covers": [
          {
            "gen": "NA",
            "years": [
              1994,
              1997
            ],
            "engines": [
              "BP"
            ]
          }
        ],
        "note": "Mazda's base manual for 1994–97; later model years got supplements, which we haven't checked yet."
      }
    }
  ],
  "jobs": [],
  "system": "transmission",
  "component": "reaudit-1994",
  "componentName": "Additional 1994 factory service specifications",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/at-fourth-band-adjusting-locknut-na-bp/"
}
```