# Differential side-bearing preload — bearing-cap pilot span (NA8)

Canonical URL: https://miatatorque.com/spec/differential-bearing-cap-pilot-span-na8/

Applicability: NA 1994–1997 (BP) — Actual 1994 factory evidence; other years in the approved family inferred with owner approval.

Confidence: fsm

185.428–185.50 mm

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": "differential-bearing-cap-pilot-span-na8",
  "name": "Differential side-bearing preload — bearing-cap pilot span (NA8)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NA",
      "years": [
        1994,
        1997
      ],
      "engines": [
        "BP"
      ],
      "note": "Actual 1994 factory evidence; other years in the approved family inferred with owner approval."
    }
  ],
  "kind": "non-torque",
  "value_text": "185.428–185.50 mm",
  "procedure": {
    "notes": "Set ring-gear backlash first. Tighten or loosen the adjusting nuts equally until the distance between the pilot sections of the bearing caps is within this range, then recheck backlash and tooth contact. This measured span controls side-bearing preload; it is not cap-bolt torque or a case-spreader setting. Use the correct carrier-specific procedure; the NA6 carrier has a different dimension."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-1994",
      "page": "M–41 (PDF p. 626)",
      "as_printed": "185.428—185.50mm {7.3004—7.3031 in}",
      "verified_years": [
        1994,
        1994
      ],
      "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": "driveshaft-differential",
  "component": "differential-inspection",
  "componentName": "Differential overhaul inspection and selection",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/differential-bearing-cap-pilot-span-na8/"
}
```