Special tools to grease U joints
It’s important to grease U joints to extend their life especially if you
do off-roading. But many times the zerk fitting is located in the cross of the U joint, making it impossible to fit a traditional grease gun coupler on to the zerk. That’s where you need a special grease gun needle adapter.
Choose from different grease gun needle adapter styles
Grease gun needle adapters come in two basic styles: screw on and snap on. The screw on styles require you to remove the coupler from the end of your grease gun hose or tube so you can screw on the needle adapter. The snap on style has a zerk fitting on one end so it snaps right onto your couple.
The screw on style is more rigid and won’t leak grease, while the snap on style is prone to leaking grease at the coupler/zerk connection. It’s not as rigid as the screw on style but it’s a lot more convenient.
Choose grease gun needle adapter needle length
The most common needle adapters have a 4-in. needle, but some adapters are about 1-in. Choose a needle adapter that can reach into the U joint.
How to inject grease into a U joint
Simply press the needle into the zerk fitting so it displaces the ball bearing seal. Then pump in the grease. Some will seep out, don’t worry about it. Click on this video for more information.
©, 2017 Rick Muscoplat
Posted on by Rick Muscoplat