Tags can vary quite a lot pending the turbocharger manufacturer, country in which it was manufactured, year in which it was manufactured as manufacturers tend to change their style of tag over time or by OEM requirements. Some turbo manufacturers such as IHI prefer to cast/engrave the turbocharger identification details on the compressor cover rather than use a tag.
Model Number or Type:
This generally indicates the general size and/or type of turbocharger within a manufacturers range of turbochargers but not a specific turbocharger.
OEM Part Number:
The specific part number of this turbocharger within the manufacturers specific range of turbochargers as mentioned above. This is best form of identification of your turbocharger for turbocharger specialists to identify your turbocharger.
The specific number for a specific turbocharger for the manufacturers reference to tell them from their records when the turbocharger was manufactured and/or when sold and to whom.
Customer Part Number aka OE Part Number:
This is the part number assigned to the turbocharger for a specific vehicle for a vehicle manufacturer. The tag may also show the logo of the vehicle manufacturer along with the turbocharger manufacturer. Performance or generic turbochargers will not have an OEM number.
How do you identify your turbocharger if the tag is missing?
Vehicle model, engine model and build date all assist in identifying turbochargers however I'm always reluctant to ship out a new or exchange turbocharger without the proper tag numbers since sometimes an owner or previous owner may have retrofitted a different type of turbocharger to the vehicle.
An emailed or faxed image together with the vehicle details can assist in identification. In most cases we can tell you what type of turbocharger it is by just looking at it on our bench from years of experience however when it is an uncommon turbocharger missing a tag we may have to remove the compressor cover and turbine housing to measure the wheels to aid in its identification.
Example ID Tags:
The first two tags; ie Garrett & 3K Turbos are normally found riveted to the side of the turbo core or front of the compressor cover.
The third example ie IHI Turbo is cast on to the compressor cover & details inscribed.