Axle problem
#1
#2
Have heard this several times before especially on after market drive shafts.Sounds like the circlip at the end of the plunging joint isn't locking into the gear groove correctly or possibly it may be a little smaller than the oem circlip.You might see if a dealer has one in stock and give it a try.Hold the drive shaft straight,splines lined up and have someone pop the end of the shaft with a dead blow hammer or block of wood and a hammer to seat the circlip.1350042 SPRING-RING
#4
#5
This same exact thing happened to me. I figured it out finally and it WAS NOT the clip. It turned out to be a slightly shorter CV axle that was sold to me as a replacement part. I took off the still functional CV axle and did a measurement. Sure enough the cheapy ebay replacement was significantly shorter! I should have done a video on this to help ones out in the future. But I'd be willing to bet this is your issue.
#7