* Clunking or popping noise: This is often the most noticeable symptom. You'll hear a distinct clunking or popping sound, especially when turning, going over bumps, or accelerating/decelerating. The noise might be coming from the front or rear, depending on which U-joint is failing.
* Vibration: A failing U-joint can cause a noticeable vibration, particularly at certain speeds. This vibration might feel like it's coming from the drivetrain and could increase with speed.
* Difficulty shifting: In some cases, a severely worn U-joint can make shifting gears more difficult or cause the transmission to feel sluggish.
* Wobbling driveshaft: Visually inspect the driveshaft. If you see any play or wobbling in the driveshaft, especially near the U-joints, it's a strong indicator of a problem. You might need to jack up the vehicle to properly inspect this. Caution: Always use jack stands and follow safe jacking procedures.
* Grease leaks: While not always present, a failing U-joint might leak grease. Look for grease around the U-joint itself.
To be certain: While the above symptoms strongly suggest a failing U-joint, the only way to be absolutely sure is to have a mechanic inspect the U-joints. They'll be able to check for play in the joint by grasping the driveshaft and attempting to move it. Excessive movement indicates a worn U-joint that needs replacing.
Important Note: Driving with a severely worn U-joint is dangerous. It could lead to driveshaft failure, potentially resulting in a loss of control and an accident. If you suspect a problem, get it checked out by a mechanic as soon as possible.
