How to identify your turbocharger?

Identifying a turbocharger correctly usually involves checking several physical and informational details, because many models look very similar. Here’s a step-by-step guide you can follow:

1. Look for the ID plate or tag

Most turbos have a metal ID plate or a stamped marking on the compressor housing or the bearing housing (center section). This will usually show:

• Turbo model number (e.g., GT1749V, HX35, TF035)

• Part number (often from Garrett, BorgWarner, Holset, IHI, Mitsubishi, etc.)

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• OEM number (from the vehicle manufacturer)​

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Clean the plate if it’s dirty — numbers are often faint.

2. Check casting number

If the ID plate is missing, look for casting or embossing marks on:

• Compressor housing

• Turbine housing

• Center housing (CHRA)

Casting numbers are not always the actual part number, but they can help cross-reference.

3. Measure the turbo

Take compressor wheel inducer/exducer diameters and turbine wheel diameters with calipers.

These measurements can narrow down possible models when cross-referencing.

4. Note the turbo type & features

• Wastegate type: Internal wastegate, external wastegate, or VNT (variable nozzle turbine).

• Mounting flange: T25, T3, T4, V-band, etc.

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• Compressor inlet/outlet size and turbine inlet/outlet size.

5. Cross-reference with catalogs

Use manufacturer catalogs or online turbo databases to match numbers and measurements.

For example:

• Garrett: Use the Garrett Aftermarket lookup.

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• BorgWarner: Check their online catalog by serial or part number.

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• Holset: Serial number lookup on Cummins Holset site.

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Pro tip

If you have only the vehicle info (make, model, year, engine code), you can work backwards from OEM parts catalogs to find the matching turbo model.