There are three sources of vibrations in a 2002 heavy duty Silverado truck. Tire balance is the most common; however, there are severe tire problems that are very hard to detect. Brakes are another source of vibrations. The least common vibration problems are drive line-related. Problems here can be especially unsettling due to the extreme vibrations they can cause. Engines can cause shaking due to misfire, but these problems are present when idling. These are easily detected and more closely related to a jerking and sputtering sensation when accelerating.
Elevate the rear of the truck with a jack and place jack stands under the rear axle. Lower the truck onto the stands. Press the brake pedal and start the truck. Slowly release the brake pedal and allow the rear tires to spin. If the vibration is present, the problem is isolated to the rear tires or drive line. If the vibration is not present, the problem is isolated to the front tires or brakes.
Grip the drive shaft from underneath the truck and attempt to move it back and forth. Pay particular attention to where the transmission and rear end yokes are coupled by universal joints, commonly called U-joints. Slackness in these joints can cause severe vibrations. The drive shaft must be firm without any backlash. Have an assistant hold one tire steady. With a light back and forth motion, rock the other tire while watching the drive shaft. If there is any backlash or movement in the universal joints, they must be replaced.
Raise the front of the truck with the jack and place jack stands under the frame. Lower the truck onto the stands. Have an assistant lightly rock the steering wheel back and forth. Inspect each tie rod end for slackness. Replace any defective tie rod.
Grip a front tire at the 12 o'clock and 6 o'clock positions. Attempt to rock the tire back and forth to test the wheel bearings. The front wheel bearings should hold the tire and wheel firmly in place. Repeat the process with the opposite tire. Wheel bearing and tie rod failures can create an oscillation or wobbling feeling in the steering wheel.
Shine a flashlight onto the front and back of each wheel and tire and look for bent or damaged wheel rims. Inspect the tires for sidewall bulges. Closely inspect each tire for scalloped or irregular tread wear. The steel belts inside of a tire can separate and create vibrations that are hard to isolate. Even though at first glance the tire may appear fine, it can be severely damaged. Closer inspection is necessary. Look for bulges in the tire sidewall. If present, the sidewall cords have separated. Inspect the tread area where steel belts may have broken and bulges have appeared. Look for missing tread. Any number of road hazards can damage tread. In all cases, the tire must be replaced.
Drive the truck and apply the brake pedal. If the steering wheel jerks back and forth or any type of vibration is present only when braking, the problem is isolated to the brake system. Usually one or more of the brake rotors are warped. Repair the brakes as needed.
