Quick Checks

1. 24-80 km/h (15-50 mph): With light acceleration, a moaning noise is heard, and possibly a vibration is felt in the floorpan. It is usually worse at a particular engine speed and at a particular throttle setting during acceleration at that speed. It may also produce a moaning sound, depending on what component is causing it. Refer to Pinpoint Test B.

2. High Speed: With slow acceleration and deceleration, a shake is sometimes noticed in the steering wheel (3600)/ steering column tube (3514), seats, floorpan, trim panels or front end sheet metal. It is a low frequency vibration (around 9-15 cycles per second). It may or may not be increased by applying brakes lightly. Refer to Pinpoint Test A.

3. High Speed: A vibration is felt in the floorpan or seats with no visible shake, but with an accompanying sound or rumble, buzz, hum, drone or booming noise. Coast with clutch depressed or transmission control selector lever in NEUTRAL and engine idling. If vibration is still evident, it may be related to wheels, tires, front disc brake rotors (1125), rear disc brake rotors (2C026), rear brake drums (1126) wheel hubs (1104) or wheel bearings (4000). Refer to Pinpoint Test A.

4. O-High Speed: A vibration is felt whenever the engine reaches a particular rpm. It will disappear in NEUTRAL coast. The vibration can be duplicated by operating the engine at the problem rpm while the vehicle is parked. It can be caused by any component, from the accessory drive belt (8620) to the clutch or torque converter which turns at engine speed when the vehicle is stopped. Refer to Pinpoint Test D.