# Differential side-bearing preload — bearing-cap pilot span (NA6)

Canonical URL: https://miatatorque.com/spec/differential-bearing-cap-pilot-span-na6/

Applicability: NA 1990–1993 (B6) — Actual 1990 factory evidence; other years in the approved family inferred with owner approval.

Confidence: fsm

150.20 mm +0/−0.72 mm (5.913 in +0/−0.028 in)

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-na6",
  "name": "Differential side-bearing preload — bearing-cap pilot span (NA6)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NA",
      "years": [
        1990,
        1993
      ],
      "engines": [
        "B6"
      ],
      "note": "Actual 1990 factory evidence; other years in the approved family inferred with owner approval."
    }
  ],
  "kind": "non-torque",
  "value_text": "150.20 mm +0/−0.72 mm (5.913 in +0/−0.028 in)",
  "procedure": {
    "notes": "NA6 carrier only. Set drive-pinion/ring-gear backlash, then tighten both adjusting nuts equally to obtain this distance between the pilot sections of the bearing caps. Preserve the backlash setting while adjusting side-bearing preload. This span is not bearing-cap bolt torque; do not substitute the larger NA8/NB carrier dimension. The asymmetric tolerance is retained as printed."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-1990",
      "page": "M–41 (PDF p. 424)",
      "as_printed": "150.20 +0/−0.72mm\n(5.913 +0/−0.028 in)",
      "verified_years": [
        1990,
        1990
      ],
      "document": {
        "id": "fsm-1990",
        "tier": 1,
        "title": "1990 Mazda MX-5 Miata Workshop Manual",
        "part_number": "1193-10-89C",
        "covers": [
          {
            "gen": "NA",
            "years": [
              1990,
              1990
            ],
            "engines": [
              "B6"
            ]
          }
        ],
        "url": "https://archive.org/details/1990-mazda-mx-5-miata-workshop-manual_202411"
      }
    }
  ],
  "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-na6/"
}
```