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Vehicle and Engine Certification

Light-Duty: Family Naming Conventions

To determine Positions 1-4 of your Durability Group name, see:

Use the table below to create Positions 5-12:

Location in
Durability Group Name
Category Code/
Description or Instructions
Position 5 Combustion
Cycle Code
2 Otto cycle — two stroke
G Otto cycle — four stroke
A Diesel cycle — two stroke
D Diesel cycle — four stroke
E Dedicated electric
H Hybrid electric with otto cycle — four stroke engine (includes PHEV vehicles)
J Hybrid electric with diesel cycle — four stroke engine (includes PHEV vehicles)
C Fuel cell
Position 6 Engine Type
P Piston
R Rotary
E Electric (including fuel cell)
H Hybrid electric (including PHEV)
A Other
Positions 7-9
(For positions
8 & 9, add
second &
third fuels
Fuels Used
G Gasoline
D Diesel
M Methanol
E Ethanol
V Electric (power grid electricity)
I Hydrogen
N Not applicable (for second and third fuels in Positions 8 and 9)
Position 10   * If applicable, indicate manufacturer-assigned battery code.
Enter a valid character in order to provide a unique identification for your family name.
Positions 11-12   ** Enter any combination of valid characters in order to provide a unique identification for your family name.
If applicable, include manufacturer-assigned catalyst code.