# Differential side-gear thrust-washer selection (NB2 open differential)

Canonical URL: https://miatatorque.com/spec/differential-side-gear-thrust-washer-selection-nb2/

Applicability: NB 2001–2005 (BP-Z3, open) — Actual 2005 factory evidence; other years in the approved family inferred with owner approval.

Confidence: fsm

Mark 0: 2.00 mm; mark 0.5: 2.05 mm; mark 1: 2.10 mm; mark 1.5: 2.15 mm; mark 2: 2.20 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-side-gear-thrust-washer-selection-nb2",
  "name": "Differential side-gear thrust-washer selection (NB2 open differential)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NB",
      "years": [
        2001,
        2005
      ],
      "engines": [
        "BP-Z3"
      ],
      "diff": [
        "open"
      ],
      "note": "Actual 2005 factory evidence; other years in the approved family inferred with owner approval."
    }
  ],
  "kind": "non-torque",
  "value_text": "Mark 0: 2.00 mm; mark 0.5: 2.05 mm; mark 1: 2.10 mm; mark 1.5: 2.15 mm; mark 2: 2.20 mm",
  "procedure": {
    "notes": "Open differential only. Select the thrust washers required to achieve side-gear/pinion-gear backlash of 0–0.1 mm. Mark numbers identify thickness choices; they are not backlash measurements. Follow the full factory differential reassembly procedure and secure the pinion-shaft knock pin as specified."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-2005",
      "page": "Thrust Washers (Standard) Assembly Note (PDF p. 1201)",
      "as_printed": "Thrust washer thickness\nIdentification mark   Thickness\n0   2.00 mm {0.0787 in}\n0.5   2.05 mm {0.0807 in}\n1   2.10 mm {0.0827 in}\n1.5   2.15 mm {0.0846 in}\n2   2.20 mm {0.0866 in}",
      "verified_years": [
        2005,
        2005
      ],
      "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": "driveshaft-differential",
  "component": "differential-inspection",
  "componentName": "Differential overhaul inspection and selection",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/differential-side-gear-thrust-washer-selection-nb2/"
}
```