How to Decode Numbers on Buick Cars

Buick muscle cars can be accurately de-coded and authenticated in a matter of minutes if you know where to look.

With classic cars bringing $100,000 and up at classic car auctions and investors buying up muscle cars as if they were corporate stocks and bonds, the term "numbers matching" gets thrown around a lot. Many people use the term, but very few people know what it even means. When cars are built on an assembly line, they have numbers assigned to different parts of the vehicle. This allows the builder to assure the correct parts were installed on the properly optioned car. This is how you can tell if that Buick GS is real or just a clone of the muscle car.

Things You'll Need

• Buick car
• GM code book
• Magnifying glass

Instructions

1. Open the hood. With the car parked and the parking brake applied, open the hood. This aids in finding the VIN information as it is often shielded by the back edge of the hood.

2. Identify the Vehicle Identification Number (VIN) number. This is located on the bottom edge of the windshield on the driver's side. It will be a small metal tag riveted onto the dash board and it will contain 17 characters consisting of numbers and letters.

3. Copy the numbers. Write the VIN number on a piece of notebook paper with a pen. This will make it easier to check against the code book. Often times, it is easiest to read the number through a magnifying glass as the characters are small and difficult to read.

4. Decode the VIN. The first character represents the country of build. For Buick it would be a 1 or 4 denoting USA. The second represents the manufacturer, a 4 represents Buick. The third represents the vehicle type or manufacturing division. The fourth through the eighth represent the vehicle's features, such as body type, engine, model and series. The ninth is an accuracy check verifying the previous numbers. The accuracy formula is detailed in the code book. The tenth represents the model year. The eleventh represents the assembly plant. The twelfth through the seventeenth represent the sequence in which the vehicle rolled off of the assembly line.

5. Check against the title. Compare your findings against the title and verify that the description on the title reflects what you have found by deciphering the VIN. For example, if the title says that the car is a Buick GS Skylark but the VIN says it is a base model six-cylinder Skylark coupe, you have a switched title and/or a copycat clone car not worth the money of the original.

Tips & Warnings

• Taking your code book (found in any good book store or ordered through a GM dealer's parts department) with you when looking at a possible purchase, can save you thousands of dollars and headaches. It can prevent you from buying a misrepresented car.

• Never attempt to alter a car title to match what you deciphered the car to be. This is a felony and can be punished with fines and imprisonment.

References

• Vehicle Identification Numbers: VIN Numbers