Ford part numbers are divided into two main categories: Engineering Numbers and Service Numbers.

The engineers will design a part and assign it an Engineering part number, which is an alphanumeric reference code used by the assembly plants. When the part is redesigned, the change needs to be noted so the Engineering part number is changed. When the part is released for service it is assigned a Service part number. It is a different number, because how a part is finished and packaged for service is different from its original production counterpart. (It’s the number used by your Ford parts man to look for your order. He doesn’t want to know about the engineering part number. However, you may need it because the engineering number is the one appearing on many parts.) This allows Ford Parts and Service to track changes affecting interchangeability by modifying the Ford Service part number. The Service part number will not change with the Engineering part number unless the change affects interchangeability. Therefore, the part numbers on the part are generally Engineering numbers while the Service part number will be on the box. There are some exceptions, such as a whole grouping of parts or a kit. Engineering and Service numbers decode the same way. The difference being the fourth character of the prefix.

Part numbers consist of a prefix, a basic part number, and a suffix. An example would be F4ZZ (prefix), 6E086 (basic part number), -A (suffix).

You can use these numbers at swap meets or salvage yards to match to existing numbers you might have. You know if the basic number is the same it should be compatible if the suffix number on the part you are comparing is a later alpha character than the existing one. Early suffix designations generally begin with “A” and increment through the alphabet as design changes are made that affect interchangeability. If the suffix on the part you were looking to replace (your existing part) was an “A” you could use parts with have a “B” suffix. If the part you were looking to replace (your existing part) had a “B” suffix, a part with the “A” suffix would probably have a compatibility issue. Parts that have later suffix codes are the ones to get.

The Basics:

Ford part numbers (other than hardware parts) are coded in two basic ways:

Regular parts have a four character prefix (LFLL), a four or five digit part number, and a one-letter suffix.

Example: C5ZZ-5255-F (Exhaust “turn-down” tailpipe on ’65-66 289 4V Non-GT Mustangs)

Many body-style specific sheet metal, body, interior and trim parts use seven digits in the part number, the first two of which identify the basic body type application, with the last five (“Body Group”) identifying the specific part within a general body area. A three-letter suffix may be used, usually to indicate color.
Example: C6ZZ-6504290-BAB (Instrument Panel, 1966 Mustang, Black)

The Prefix:

The four-digit alphanumeric prefix tells the year the part was released for production, the vehicle line the part was originally released for and by what Ford engineering division (chassis, engine, body, etc.) or in the case of a service parts, the Ford car division the part is for – Ford or Lincoln-Mercury.

The 1st character of the prefix indicates the decade of design, starting with “A” for the 1940’s, B for the 1950’s, C for the 1960’s.

The 2nd character of the indicates the year within the decade, “C5” would be 1965, “F4” would be 1994.

The 3rd character of the prefix indicates the product part the part was originally designed for, with few exceptions. Note that “outside sales (code F), “Motorcraft Brand” (code P), or imported parts from Ford of Europe (code R) are identified with their product line code in the third position.

The 4th character indicates the part source, whether it is product engineering office or service part.

Code Chart:

1st – Decade Code: 2nd – Year Code: 3rd – Product Line Code: 4th – Design Responsibility Code:
B 1950 0
19X0 9 Aerostar A Light Truck Engineering
C 1960 1 19X1 7 Explorer/Ranger B Body Engineering
D 1970 2 19X2 0 Continental C Chassis Engineering
E 1980 3 19X3 W Cougar D Overseas Product Engineering
F 1990 4 19X4 U Econoline E Engine Engineering, Engine Product and Manufacturing Engineering
5 19X5 C Escort F Electronics Division, Product Engineering Offc.
6 19X6 B Festiva G Electronics Division, Arbor Plant
7 19X7 A Crown Victoria H Climate Control Division, Product Engineering Offc.
8 19X8 T Lt. Truck/Bronco J Ford Customer Svc. Division Parts and Accessories Engineering Offc.
V Lincoln K Import Component Engineering, Body Engineering
L Mark VIII L Ford Customer Svc. Division Power Products/Ford Cust. Svc. Engineering
H Medium Truck M Performance Operations, Special Vehicle Operations
J Power Products P Transmission and Axle Product and Manufacturing Engineering (Automatic Transmissions)
M Grand Marquis R Transmission and Axle Product and Manufacturing Engineering (Manual Transmissions)
P Motorcraft Brand S Light/Heavy Truck Engineering, Truck Special Order Department
Z Mustang T Heavy Truck Engineering
2 Probe U Electrical and Fuel Handling Division, Product Energy Office
4 Sable V Domestic Special Order Engineering Section, Car Special Order and Special Vehicle Engineering
D Taurus W Transmission and Axle Product and Manufacturing Engineering (Axle and Driveline)
F Outside Sales X Plastic and Trim Products Division
3 Tempo/Contour/Mystique Y Ford Customer Service Division (Lincoln and Mercury), Product Analysis and Publications
R #1 Z Ford Customer Service Division (Ford), Product Analysis and Publications
Thunderbird 8
Electric Vehicle Engineering
6 Topaz 5 Ford PN96/UN98 Platform Engineering
K Tracer
X Villager
8 Windstar
Y Electric Vehicle
Q DEW98 Platform
1 F350/Excursion


1999+ models:

Year/Decade Codes: Product Line Codes: Design Responsibility Codes:
A 2010 S1 Aspire A Advanced Vehicle Technologies Core Operations
B 2011 S2 Contour B Not Assigned
C 2012 S4 Escort/Focus C Chassis Operations
D 2013 S5 Ka D Overseas Product Engineering
E 2014 S6 Fiesta E Engine Engineering, Engine Product and Manufacturing Engineering
F 2015 S7 Mondeo F Electronics Engineering Operations
G 2016 S8 Probe G Not Assigned
H 2017 S9 Mystique H Climate Control Operations
J 2018 M1 Tracer J Ford Customer Service Division Parts and Accessories Engineering
K 2019 F1 Taurus K Import Release Section
L 2020 F2 Windstar L Ford Customer Service Division Power Products Engineering
M 2021 F3 Continental M Special Vehicle Operations
N 2022 F4 Sable N Not Assigned
P 2023 F5 Villager P Transmission and Axle Product and Manufacturing Engineering (Automatic Transmission)
R 2024 F6 Thunderbird R Transmission and Axle Product and Manufacturing Engineering (Manual Transmission)
S 1995 F7 EN158 S Light and Heavy Truck Engineering/Truck Special Order Department
T 1996 F8 FW178 T Not Assigned
V 1997 L1 Bronco U Electrical and Fuel Handling Division
W 1998 L2 Explorer V Domestic Special Order Engineering Section
X 1999 L3 F150/F250 W Transmission and Axle Product and Manufacturing Engineering (Axle and Driveline)
Y 2000 L4 Maverick 4X4 X Plastic and Trim Products Operations
1 2001 L5 Ranger Y Not Assigned
2 2002 L6 Aerostar Z Ford Customer Service Division Product Analysis / Ford Service Parts
3 2003 R1 Aston-Martin 1 Vehicle Center 1
4 2004 R2 Falcon 2 Vehicle Center 2
5 2005 R3 Mustang 3 Vehicle Center 3
6 2006 R4 Scorpio 4 Vehicle Center 4
7 2007 R5 Fairlane 5 Vehicle Center 5
8 2008 R6 LTD 6 Vehicle Center 6
9 2009 R8 Jaguar S-Type 7 Not Assigned
R9 Mark VIII 8 Electric Vehicle Engineering
W1 Town Car 9 Not Assigned
W2 Cougar
W3 Grand Marquis
W4 DEW98
W5 EW171
W6 Thunderbird RWD
W7 EN114 Crown Vic
W8 Jaguar XK8/XKR
W9 Jaguar XJ-Series
C1 Transit
C2 Econoline
C3 Medium Truck
C4 L-Series/Cargo-CF Series Truck
U1 Power Products
U2 Motorcraft Brand
U3 Outside Sales
U4 #3


Suffix (Release / Revision):

A part-number suffix generally tells you the change level of a part, regardless of whether it is applied to the casting, the finished part or the service part. A suffix of A applies to a part produced as it was originally designed, B indicates it was changed once, C indicates it was changed twice and right through the alphabet in sequence, excluding the letter I. When the alphabet as been gone through once, the suffix grows to two letters and starts over as AA, AB, AC and so on.

How does a change affect the other two numbers? A service part and its number can change independently of the casting part and its number simply because it comes after these two in the scheme of things. Using the same reasoning, a finished, or engineering part can change independently of the casting, but not of the service part. A casting affects both the finished and the service parts. This is why the suffixes of all three numbers rarely match.

However, sometimes a single letter indicates specific application. For example: 9425-A is an intake manifold for a 289-2V engine, whereas a 9425-B is for a 289-4V engine, and a 9425-C is for a 351C-4V engine.

The suffix can also refer to the color or finish of the part, or the left- or right-hand use of a part. In most cases if the part is for left-hand use, the basic number ends in a odd number and the basic number for the right-hand part ends in a even number. For example, the 1969 Mustang front fender wheelhouse molding C9ZZ-16038-A is the right-hand molding and C9ZZ-16039-A is the left-hand molding. Notice there is no body code in front of the basic number 16038. The reason for this is that a change in body style did not effect the application of this part…that is, all ’69 Mustang body styles used the same wheelhouse molding.

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