For 1990-2009 cars

# Tire/Wheel Characteristics (Vibration, Balance, Shake, Flat Spotting) of GM Original Equipment Tires

Subject: | Info - Tire/Wheel Characteristics (Vibration, Balance, Shake, Flat Spotting) of GM Original Equipment Tires

Models: | 2008 and Prior Cars and Light Duty Trucks (Including Saturn)

| 2008 and Prior HUMMER H2, H3

| 2005-2008 Saab 9-7X

This bulletin is being revised to include additional information and model years. Please discard Corporate Bulletin Number 03-03-10-007B (Section 03 - Suspension).

The purpose of this bulletin is to help explain that , under certain circumstances, a customer may notice a slight tire shake within the first few miles/kilometers of vehicle operation.

Tires may be designed with a nylon overlay configuration engineered to enhance the tire's integrity at high speeds. This allows the tires to be driven at higher speeds without excessive heat buildup.

Important: Before measuring tires on equipment such as the Hunter GSP 9700, the vehicle MUST be driven a minimum of 16 km (10 mi) to ensure removal of any flat spotting. (The tendency to "flat spot" is less likely as the tire accumulates mileage.)

When parked overnight, or for a period of time, the tires may set (flat spot) and require a few miles/kilometers before heating up to their normal operating temperature. Until the tires warm up, a slight tire shake may be felt but should subside quickly.

Important: DEALERS SHOULD REFRAIN FROM ATTEMPTING REPAIRS OR REPLACING COMPONENTS.