UJ (universal joint) - what is it?
Universal joints (UJs) also known as spiders, are mounted on the propeller shafts that link the transfer case to the front and rear axles.
The UJ is a cross-shaped component with a needle-roller bearing cup at each extremity, Just like a CV joint, it absorbs movement between the chassis and the transmission.
Why replace a UJ?
You can easily diagnose a worn or tired UJ by listening out for unsual noises. Often starting as a light rumble the noise will progressively become harsher and louder. You will also notice vibrations and even a knocking sound as the propeller shaft takes up drive. The diagnosis can be confirmed by getting under the car and manually manipulating the drive shafts.
In this article, we will take your through, step-by-step to show you how easy it is to change a UJ on your 4x4.
For the purposes of this tutorial we are working on a 3.0-liter Nissan Patrol Y61.
However, the same procedure is valid for almost all 4x4 models.
TOOLS
To replace the UJ on your 4x4, you will need the following:
. 2 17mm flat spanners
. Hammer
. F-clamp
. Flat screwdriver
. Vice
. Length of tubing
. Sandpaper
. Grease
DIFFICULTY
To give you an idea of the difficulty level of our tutorials, we rate them from 1 to 5.
Replacing a UJ on a 4x4 is a level 2 job.
WORKSHOP
1 - Undo the 4 bolts at the axle end of the prop shaft with the 17mm spanner.
2 - Now do the same at the transfer box end of the shaft. Be sure to support the shaft so that it doesn't fall.
3 - Use the flat head screwdriver to prise off the 4 clips that hold the UJ.
4 - Use the tube to push out the old roller bearing cups
5 - This UJ really had reached the end of the road!
6 - Thoroughly clean the end of the prop shaft using the sandpaper then add some grease. This will help the new bearing cups to fit.
7 - Insert the new UJ as shown then push the new needle bearing cup into place.
8 - Now fit the second bearing cup.
9 - Now use the F-clamp to help push the cups into position.
10 - Refit the first 2 clips.
11 - Repeat the same steps for the other 2 bearing cups. When you have fitted the last clips, grease the UJ.
12 - Now repeat the procedure for the other end of the prop shaft.
PARTS
Choose the right UJ for your propeller shaft
Credits: Thanks to Jeff - www.patrol-gr.net
Please note: Euro4x4Parts publishes this information to help its customers but cannot be held responsible for the advice given here and practical consequences therin.
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Please note: Euro4x4parts publishes this information to help its customers, but cannot be held responsible for the advice given here and their consequences when used.