Vehicle Identification Number (VIN)

One of these most important pieces of information you may need to find a correct part for a particular application is the 17-digit Vehicle Identification Number (VIN). The VIN number can be found on a plate at the base of the windshield on the driver's side. It may also be included on a separate tag in the engine compartment or elsewhere on the body or frame.

The place of each letter or number in the VIN code reveals important information about where the vehicle was made, when it was made, the type of engine in the vehicle, the model or series of the vehicle and the production sequence of the vehicle.

* The first three letters or numbers in the VIN code reveals the country of origin, the vehicle manufacturer and vehicle type.

* The digit or number that identifies the engine depends on the year and make. For 1981 and newer vehicles, the engine code is usually the eighth digit (Chrysler, GM and Ford), but may be the fourth digit (Jeep 1981-89). On 1980-81 Chryslers, the engine code is the sixth digit. On 1967-80 Fords, it is the fifth digit. On 1972-80 GM and 1974-80 Dodge and Plymouth models, it is the sixth digit.

* The tenth digit is the year the vehicle was made (1981 and newer vehicles). On 1980 and older vehicles, the model year may be indicated by any of the first six digits depending on the make.

* The last six digits are the vehicle production numbers. Identifying the vehicle year and engine code is often necessary when looking up ignition, fuel, emission and engine components. So it's important to know how to use the VIN code because vehicle manufacturers sometimes make running production changes in mid-year (import manufacturers do this frequently). An application listing may say that a part only fits vehicles up to a certain VIN number or build date.

OTHER WAYS TO IDENTIFY COMPONENTS
In addition to using the VIN number, many parts may require you to refer to a casting number on the component itself, or an OEM label or manufacturing tag on the old component. Using the OEM part number allows you to correctly identify the application so you can find the right replacement part.

The underhood emissions decal is another source of vehicle information. It identifies the engine displacement and calibration code, along with other necessary emission system information. It may also list the type of spark plugs required. This decal is usually found on the underside of the hood, but may be located elsewhere in the engine compartment.

Visually comparing parts can also help in the identification process. If possible, compare the original part to the replacement part to make sure bolt holes and other fastener locations, fittings, etc. are the same. Any dimension that is critical to the installation of the part should match the original. This includes shaft and pulley diameters, spline counts, thread pitch and length, gasket mating surfaces and other physical connections.

Due to consolidation, some aftermarket parts may have a somewhat different appearance than the original part they replace. Others may require adapters or other modifications to be installed. This is often the case with electrical components such as alternators and exhaust system components such as mufflers and pipes.

If a replacement part requires adapters or other modifications, these should be described in the parts catalog or electronic database. What's important here is to make sure that your customer gets everything he needs to install the replacement part or parts.

BODY STYLES
There are two basic types of vehicle construction used today: frame and unibody. Vehicles with frames include most trucks, SUVs and full-size vans. A frame provides added strength and rigidity as well as weight-carrying capability. Unibody construction, which only uses subframes or partial frames for the front and rear suspension members, is lighter and is used in most passenger cars.

Basic body styles include coupe (two-door), sedan (four-door), convertible (soft top), wagon (extended roofline with no separate trunk, or minivans), and hatchback (rear trunk lid and window combined). A liftgate is a rear door on a minivan or SUV that opens vertically.

Vehicle manufacturers also use their own body family codes that are based on common vehicle platforms or model lines. Vehicles within a given product line typically share common mechanical components, but external body panels and trim may be different. This applies mostly to General Motors and Chrysler vehicles.

For example, GM "W-body" applications include the Chevrolet Lumina, Pontiac Grand Prix, Oldsmobile Cutlass Supreme and Buick Regal. Chrysler "LH-body" applications include the Concorde, Intrepid, LHS, Vision and 300M.

PAINT CODES
When matching paint colors, the OEM paint code from the Vehicle Identification Plate (VIP) is needed. The VIP plate may be located under the hood, on the firewall, in the doorjamb or trunk (there is no standard location for this information).

Compare the code with the listings in a color book for the year, make and model of the vehicle. If possible, compare a paint chip to the vehicle itself because the vehicle may have been repainted.

Popular colors on recent models are usually available ready-mixed in pints, quarts or gallons, but colors for older vehicles, less popular models or custom colors have to be custom mixed.

1. A vehicle's "VIN" number can usually be found where?
a. On a plate at the base of the windshield
b. On the engine block
c. On the license plate
d. In the owners manual

2. The VIN number can usually provide all of the following EXCEPT:
a. Year of vehicle
b. Make of vehicle
c. Engine code
d. Paint code

3. Since 1981, all VIN numbers have how many digits?
a. 12
b. 15
c. 17
d. 19

4. Counterman A says the 10th digit in the VIN code on 1981 and newer vehicles reveals the year it was made. Counterman B says on 1980 and older vehicles, the year of manufacture may be indicated by any of the first six digits depending on the make. Who is right?
a. Counterman A only
b. Counterman B only
c. Both Counterman A and B
d. Neither one

5. All of the following statements about a vehicle's "emissions decal" are true EXCEPT:
a. It may be located on the engine or in the engine compartment
b. It tells when a vehicle last had an emissions test
c. It tells what type of emissions system is on the engine
d. It may include tune-up specifications

6. An "OEM part number" can be used for what?
a. To identify a component
b. To cross-reference replacement parts
c. To order parts from a vehicle manufacturer
d. All of the above

7. A vehicle with "unibody" construction:
a. Has no separate frame
b. Is made in one-section
c. Uses universal parts
d. Has replaceable quarter panels

8. A "coupe" has what?
a. Two doors
b. Three doors
c. Four doors
d. Convertible top