VIN Derivative

All engines and transmissions are stamped with a partial Vehicle Identification Number (VIN), which is derived from the complete VIN. A VIN derivative contains the following nine positions:
^ Position 1 is the GM division identifier:
6 = Cadillac
^ Position 2 is the model year:
Y = 2000
^ Position 3 is the assembly plant code:
U = Hamtramck, MI
M = Lansing, MI
^ Positions 4-9 contain the assembly plant sequential number for the vehicle.

A VIN derivative can be used to determine if a vehicle contains the original engine or transmission, by matching the VIN derivative positions to their accompanying positions in the complete VIN:
^ VIN derivative position 1 = VIN position 3
^ VIN derivative position 2 = VIN position 10
^ VIN derivative position 3 = VIN position 11
^ VIN derivative positions 4-9 = VIN positions 12-17