Proper Lubrication of U-joint: What Does Fresh Grease at Trunnion Seals Indicate?

What does the appearance of fresh grease at all four trunnion seals after lubricating a U-joint indicate?

The appearance of fresh grease at all four trunnion seals after lubricating a U-joint typically signifies which of the following?

a) the U-joint has been properly lubricated

b) the bearings are worn and should be replaced.

c) the seals are worn and should be replaced.

d) the trunnions are worn and the U-joint should be replaced.

When lubricating a U-joint, if fresh grease appears at all four trunnion seals, it indicates that the U-joint has been properly lubricated. This is a positive sign that the lubrication process was successful and the grease has reached all necessary parts of the U-joint.

The presence of fresh grease at the trunnion seals is a good indication that the bearings inside the U-joint have received adequate lubrication. This does not necessarily mean that the bearings, seals, or trunnions are worn out.

Inspecting the U-joint for wear or damage is still necessary even if fresh grease is visible at all four trunnion seals. However, in general, this outcome suggests that the U-joint has been properly lubricated and no immediate action is required unless there are visible signs of wear or damage.