Inspect/Service/Replace

• Inspect the driveshaft, carrier bearing, companion flange, pinion seal, pinion bearing, and transmission housing and bearing.
• Your car may contain more than one U-joint. Be sure to check them all.
• A failed U-joint or damaged drive shaft can exhibit a variety of symptoms. A clunk that is heard when the transmission is shifted into gear is the most obvious. You also encounter unusual noise, roughness, or vibration.
• As a general guide, a worn U-joint is most noticeable during acceleration or deceleration and is less speed sensitive than an unbalanced tire (commonly occurring in the 30 to 60 mph 50 To 100 Km/H range) or a bad wheel bearing (more noticeable at higher speeds).
• Inspect the U-joint's grease seals for signs of rust, leakage, or lubrication breakdown.
• Check for excessive joint movement by firmly grasping and attempting to rotate the coupling yokes back and forth in opposite directions. If any perceptible trunnion-to-bearing movement is felt, the joint should be replaced.

Testing U-joints for signs of obvious damage.