Where the number comes from
| Source | Reliability | Notes |
|---|---|---|
| Stamped or labelled on the old part | Highest | Most reliable; remove the part to read it |
| Workshop manual or EPC | High | Accurate if the market and year are correct |
| Photo of the old part or VIN | Medium | Send a clear photo; supplier can check |
Common formats
| Brand family | Example | Structure |
|---|---|---|
| Japanese (Toyota) | 44250-25030 | First 5 digits = component group; last 5 = specific part |
| VW Group | 1K0 820 803 L | Platform code + component group + part + revision letter |
| US | 52013466AM | Numeric part number + version suffix |
| Korean | 57700-4H100 | 5-digit group + 5-digit part |
| Compressor body model | 7SEU17C / PXC16 / 7SBU16C | Compressor maker’s body model — not an OEM number |
Why one part has several numbers
- Supersession: the part is revised and the suffix letter moves on (VW Group uses the trailing letter).
- Market-specific numbers: the same part can carry a local number in another country.
- Supplier cross-references: TRW, ZF, Denso and others publish their own numbers.
- Assembly vs component: the assembly number and the internal part number are different.
Four-step confirmation
| Step | Check | Why |
|---|---|---|
| 1 | Model, year, engine | The same model often changes part mid-life |
| 2 | LHD or RHD | Usually two separate catalogues |
| 3 | Original part number | Fastest way to lock the reference |
| 4 | Key dimensions and options | Travel, ports, pulley grooves, electronic damping |
Common mistakes
- Ordering by model only, without the year.
- Assuming “looks the same” means interchangeable.
- Ignoring drive side and electronic options (ADS/CDC).
- Searching a compressor body model as if it were an OEM number.
Send us your chassis number or original part number and we will confirm the reference.