①Lack of lubricating oil
②The universal joint cross shaft and the needle are worn and the loose or needle is broken.
③ drive shaft spline teeth and telescopic tube spline groove wear loose
④The second shaft spline and flange spline groove of the transmission are worn out too much.
⑤loose bolts at each joint
⑥ The intermediate bearing is worn out or the bearing bracket rubber sleeve is damaged, or the bracket position is incorrect and the assembly is improper, which causes the bearing to be skewed.
⑦drive shaft is bent, sunken, and loses balance during operation
⑧drive shaft ends universal joint fork installation is not correct
⑨The balance block is detached, the flange and the shaft tube are welded and skewed, and the spline is loosened.
⑩The coaxiality of the 100,000 joint cross shaft rotation center and the transmission shaft is too large.