How to Identify a Garrett Turbo

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Where to Find the ID Tag

On most Garrett turbochargers, the identification tag is a small aluminum or stainless steel plate riveted or glued to the compressor housing, typically near the compressor inlet or on the flat boss cast into the housing. Garrett has used this convention across the GT and VNT families for decades, so units like the GT3782VA and VNT15 will usually carry their plate in this same general area. On some variable geometry models such as the GTB2260VK and GTB1756VK, the tag may instead be located on the bearing housing or on the actuator side, so it is worth rotating the unit fully before concluding the tag is missing.

In addition to the riveted plate, many Garrett units carry stamped or laser-etched numbers directly on the compressor housing or the center housing rotating assembly (CHRA). When the original tag has been removed during a prior rebuild, these stamped numbers are often the only surviving way to trace the unit. Heavy diesel applications like the GTP38 found on Ford Power Stroke engines frequently have the tag on the compressor cover facing the engine, which can make it awkward to read while installed.

Reading the Tag

A Garrett tag generally lists three key pieces of information: the model designation, the assembly part number, and the serial number. The model designation is the family name you recognize, such as GT3788VA, GT3794VA, or VNT20. The assembly part number is the most important number for an exact match, usually formatted as a multi-digit base number followed by a dash and a revision suffix, for example 743250-5025S. The leading digits identify the core program, while the suffix after the dash indicates the specific build configuration, trim, and supersession level.

The serial number is unique to each individual unit and is used for warranty and manufacturing traceability rather than identification of the part type. When interpreting the model number, note that letters such as VA, VK, and VNT indicate variable nozzle or variable geometry turbine designs, while a plain GT designation without those suffixes usually denotes a fixed wastegated or free-floating unit. The four-digit number embedded in names like GT3782 roughly reflects compressor and turbine frame sizing, but you should always confirm against the assembly part number rather than relying on the frame designation alone.

Common Identification Mistakes

• Confusing closely numbered variants such as the GT3782VA, GT3788VA, and GT3794VA, which share a frame family but use different turbine wheels, nozzle rings, and calibrations that are not interchangeable.
• Treating a superseded assembly part number as a mismatch when Garrett has revised the suffix, meaning an older dash number may have been officially replaced by a newer one for the same application.
• Mistaking an aftermarket or remanufactured unit that has been relabeled with a generic or replica tag for a genuine Garrett, when the casting and wheel details tell a different story.
• Assuming a VNT15 and VNT20 are interchangeable because both are variable nozzle units, when they differ in frame size and flow capacity.
• Identifying a turbo purely by the engine it came off, since manufacturers like Ford used the GTP38 across multiple model years with internal differences that matter for an exact rebuild.

What to Send Us

When you reach out about identifying your turbo, include as much of the following as you can:

• The full model designation (e.g. HX35, GT3782VA, S400)
• The assembly or part number, if visible on the tag
• The serial number, if present
• A clear photo of the complete tag
• A clear photo of the complete turbo
• The vehicle, engine, or equipment it came off of, if known

Email photos to [email protected], or use our Contact form and include what you know in the Turbocharger Info field — we’ll help identify it from there.

Frequently Asked Questions