What Causes Engine Vibration in Buick GL8?

[VonCora]

Here are the reasons for engine vibration in the Buick GL8: 1. High-speed vibration: Symptom: On a straight road, when the vehicle reaches around 120 km/h, it experiences vertical vibrations. In severe cases, the entire body shakes. This issue is unrelated to whether the vehicle is accelerating or decelerating and is solely speed-dependent. The cause is dynamic imbalance in large-mass, high-speed rotating components, including tires, rims, and half-shafts. During driving, these parts may deform, altering their balance. Even without obvious deformation, minor contaminants like mud can trigger vibrations. The solution is simple: replace deformed parts and perform precise dynamic balancing on the tire and rim assembly. 2. High-speed brake vibration: Symptom: On a straight road, when braking at around 120 km/h, the steering wheel vibrates with high-frequency, small-amplitude left-right movements. In severe cases, the entire body sways. This is often caused by brake disc runout. Diagnosis is straightforward: use a dial indicator to measure the disc's rotational runout. If it exceeds 0.1 mm, the disc should be precision-machined (specialized equipment is essential for accuracy). Also, check for looseness in steering linkage and ball joints, replacing if necessary. 3. Starting vibration: This affects manual transmission vehicles. Symptom: When starting from rest and gradually releasing the clutch pedal, the vehicle shakes. This occurs due to irregular wear in the clutch assembly (flywheel, clutch disc, pressure plate), causing misalignment. During engagement, the clutch disc fails to connect smoothly, intermittently slipping—resulting in a jerky motion. Replace the worn clutch components.