RPO explanation and Where to find them
A RPO is a R
ption or essentially the options that the car comes with (also called the Service Parts Identification Label). Here is what one looks like:
(1) Vehicle Identification Number
(2) Wheel Base
(3) Part Number Location
(4) Model Designation
(5) Order Number
(6) Exterior Color
(7) Paint Technology
here is a "real" one (note that this one has extra annotations):
The RPO Label or "service parts ID label" can be found on the Spare tire cover on most GM cars.
A RPO code itself is a 3 digit/character code. By looking up your RPO codes, you will be able to see almost every option that your car is built with.
For example, if your car came with the 16 inch wheels, you will see a PY0 code on the sticker. W33 means your car is a GLS.
Once you have located your codes, you can cross-reference them here: www.rpocodes.com or here: http://www.cadillacfaq.com/rpo/index.php
Where to find VIN Codes
For a breakdown on all VIN codes, go here: http://en.wikibooks.org/wiki/Vehicle...9/GM/VIN_Codes