GM Service Manual Online
For 1990-2009 cars only

Comparing the customer's vehicle to a KNOWN GOOD vehicle that is essentially identical will help determine if the customer's concern may be characteristic of a vehicle design. To arrive at a valid conclusion, the comparison must be performed under the same conditions, using the same criteria, on a vehicle that has the same option content as the customer's vehicle.

The comparison vehicle must match the customer's vehicle in the following areas:

    â€¢ Year
    â€¢ Make
    â€¢ Model
    â€¢ Body style
    â€¢ Powertrain configuration
    â€¢ Driveline configuration
    â€¢ Final drive ratio
    â€¢ Tire/wheel size and type
    â€¢ Suspension package
    â€¢ Trailering package
    â€¢ GVW rating
    â€¢ Performance options
    â€¢ Luxury options