Crack the Code. How to Decode Your Caterpillar Serial Number


A Caterpillar serial number is a unique identifier assigned to each piece of equipment manufactured by Caterpillar Inc. Understanding how to decode and interpret the serial number is important for several reasons:

The serial number helps identify the specific machine, including the model, year, and factory of manufacture. This information allows owners, operators, and service technicians to look up specifications, parts information, and service histories for that particular equipment.

The serial number format has changed over Caterpillar’s history, so knowing how to break down the serial number provides insights into when the machine was made. This can assist with determining the machine’s age, replacement part compatibility, and other factors influenced by manufacture date.

Decoding the serial number allows verification that the number on the machine matches documentation. This helps ensure the equipment has not been swapped out or incorrectly identified.

In summary, understanding Caterpillar serial numbers provides valuable insights into a machine’s identity, specifications, service history, and other important details through one unique alphanumeric sequence.

Locating the Serial Number

The serial number on Caterpillar equipment can be found in various locations depending on the type of machine. Here’s where to look:

  • On excavators, the serial number plate is typically located on the swing frame behind the operator’s station.[1]
  • For backhoe loaders, wheel loaders, and skid steer loaders, check the inside of the door frame or hood.[1]
  • On articulated trucks, motor graders, and paving products, look for a plate on the front frame.[1]
  • For engines, the serial number is often stamped directly onto the engine block.[2]
  • On older equipment, the serial number may be stamped or etched directly onto the frame.

Consult your operator’s manual if you’re having trouble locating your Caterpillar equipment’s serial number.

Serial Number Format

Caterpillar serial numbers follow a standard format that uses a combination of letters and numbers to identify key information about the equipment. The serial number is broken down into several distinct groups of digits:

The first group is the date code, which indicates the year and month the machine was manufactured. This is typically a four or five digit number, with the first two digits indicating the year and the third and sometimes fourth digits indicating the month.

The next group is the factory code, which identifies where the machine was built. Each Caterpillar factory location has its own unique code. This code is usually one or two letters.

After the factory code is the product code, which identifies the type of machine or engine. This typically consists of four or five digits unique to that particular model.

The configuration code comes next, specifying certain options or features included on that particular machine. This is commonly one letter or number.

Finally, the sequence code is a sequential serial number assigned to each individual unit as it’s manufactured. This is normally three to six digits long.

Knowing how to break down the Caterpillar serial number digit groups allows you to decode key information about your equipment right from the serial number. Understanding the formatting provides insight into when and where your machine was made, as well as the specific model type.

Date Code

The date code is the 4-digit number in positions 4-7 of the serial number. It indicates the year and month the machine was manufactured. The first digit is the last digit of the year, while the next 3 digits represent the month. For example, a date code of “9205” indicates the machine was manufactured in May 1992.

Here’s an example to decode the date code:

Serial number: CAT00389318JKR09205

Date code: 09205

Year: 2095 = 1995

Month: 0920 = May

Therefore, this machine was manufactured in May 1995.

Knowing the manufacturing date can help determine the machine’s age, find the correct parts, and evaluate service needs. According to the Caterpillar Serial Number Guide (, older machines used a different date code format prior to 1990.

Factory Code

The factory code identifies which Caterpillar factory manufactured the product. It consists of 1 or 2 digits located in the 4th and 5th position of the serial number.

Examples of factory codes include:

  • 3D = United Kingdom
  • 5Y = Japan
  • 07 = France
  • 17 = India
  • 31 = Belgium

Some of the most common factory codes are:

  • 3B = East Peoria, Illinois, USA
  • 8J = Aurora, Illinois, USA
  • 8N = Corinth, Mississippi, USA

Knowing the factory code can help determine the origin of manufacture for a Caterpillar product.

Product Code

The product code consists of 1-3 letters or numbers that identify the type of machine the serial number is assigned to. For example:

  • Excavators start with K
  • Wheel loaders start with M
  • Dozers start with D
  • Backhoes start with C

Some other common product codes include:

  • A – Articulated Trucks
  • B – Pipelayers
  • E – Electric Rope Shovels
  • F – Track Type Tractors
  • H – Harvester
  • L – Landfill Compactors
  • N – Motor Graders
  • P – Track Type Tractors
  • S – Skid Steer Loaders
  • T – Track Type Tractors
  • W – Wheel Tractor Scrapers

The product code makes it easy to identify which type of Caterpillar machine a serial number belongs to at a glance.

Configuration Code

The configuration code is a two character code that provides information about the configuration of your Caterpillar equipment. This code indicates the type of equipment, specific model, and particular features of that model.

For example, a configuration code of “CA” may indicate a Track-Type Tractor while “SL” indicates an Articulated Truck model. The letters provide specifics on the type of machine. Additionally, variations of a model may have different configuration codes to denote differences in features like engine type, hydraulic systems, emissions standards and more.

The configuration code allows you to see at a glance what machine configuration you have based on your serial number. It provides key details that distinguish between models and options without needing to look up additional specification information. When decoding your serial number, pay close attention to the configuration code as it gives you insight into your exact Caterpillar equipment.

Sequence Code

The sequence code is a unique identifier that distinguishes each individual machine manufactured at that factory. The sequence code can range from 1 to 9,999 and resets back to 1 at the beginning of each new year. This allows each factory to produce up to 9,999 machines per year with a unique sequence number.

The way the sequence code appears in the serial number format differs between older and newer Caterpillar machines:

  • For older machines (pre-1970), the sequence code is a 4-digit number embedded directly in the overall serial number.
  • For newer machines (post-1970), the sequence code is a separate 4 or 5 digit code that comes after the product code and before the validation digit.

So in the serial number format, the position of the sequence code shifted. But its purpose remains the same – to uniquely identify each machine down to the individual unit.

Validation Digit

The validation digit or check digit is the last digit of the Caterpillar serial number. It is used to validate the authenticity of the serial number to prevent fraud or tampering.

The check digit is calculated by applying a mathematical formula to all the other digits in the serial number. Each digit is multiplied by a predetermined number and the products are summed. The last digit of the total is used as the check digit.

When validating a serial number, the same formula is applied to calculate what the check digit should be based on the other digits. This calculated check digit is compared to the actual check digit in the serial number. If they match, the serial number is considered valid. If they do not match, there is likely an error or tampering of the serial number.

The check digit provides a simple and quick way to validate that a Caterpillar serial number is authentic before it is used for parts lookup or other purposes. By including this validation step, instances of fraud or reuse of serial numbers can be prevented (Source).

Decode Your Serial Number

Now that you understand the different parts of a Caterpillar serial number, you can decode your own serial number by following these steps:

  1. Locate the serial number plate on your Caterpillar equipment.
  2. Write down the full serial number as it appears on the plate.
  3. Identify the position of each code element based on the standard format.
  4. Use the information in this guide to decode each segment of the serial number.

For example, if your serial number is 6CM02536, it would decode as:

  • 6C – Product code for a 966M Wheel Loader
  • M – Built in Joliet, Illinois factory
  • 02 – Manufactured in 2002
  • 536 – Unit #536 produced that year

With some simple analysis, you now know your loader’s key specifications based on the serial number alone. This allows you to identify the correct parts, manuals, and support resources for your specific machine.

Scroll to Top