An OE number is the car maker's own part identifier. It is precise about which vehicle the part was built for, and deliberately unhelpful about almost everything else.
It identifies the application, not the maker
The number belongs to the vehicle manufacturer, not to the company that actually produced the unit. A single OE number can be served by more than one manufacturer, which is exactly why the same application often appears under several brand lines.
This is also why "which brand is it?" is a separate question from "which OE number is it?" — and why we ask both.
Formats differ by car maker
Number formats follow the issuing manufacturer's own conventions. There is no universal scheme, so a number that looks like a valid Volkswagen format will not decode as a Toyota one.
- Some makers use a long numeric block, sometimes with a group and part suffix
- Some use alphanumeric prefixes that encode a system or platform
- Some print the number in several places, with the same digits split differently
Supersessions change the number without changing the part
When a manufacturer revises a part, it often issues a new number and keeps the original in circulation for a while. Both numbers refer to the same application, and the newer one is the correct order reference.
This is the most common reason a buyer thinks they have been sent the wrong part. Send both numbers if you have them — the old one helps us confirm the match, the new one is what we order against.
What the number will not tell you
It will not tell you the output rating, the pulley diameter, the mounting orientation or whether a particular brand line is available. Those come from the catalogue entry, not from the digits.
Treat the OE number as the key to the correct record — not as a specification in itself.
Have a part number to price?
Send it over with the quantity and destination. You will get a fitment check, a unit price and a freight cost — usually the same business day.