The other day I was backing out of my driveway, and I then felt a little pop that felt like it came from the back of my truck. I had just previously changed the gear lube using redline. I have checked the U-joints and there is no play with them that I can feel. So I guess that I was wondering if anybody has any ideas as to what may be causing this.
Thanks in advance for any help.

 

If you have a limited slip rear axle did you add the required amount of friction modifier?

 

not sure if redline has the additive already in the lub for a limited slip diff, likely you will have to add a little additive to keep the diff from making that "pop" thump noise, mine has an additive to but it will make the pop/thump noise almost every time when backing while turning ,then when I go forward and turn at the same time it will do it until I straighten out

I need to add a little more additive...

 

Well yeah I did add some friction modifier when I changed the lube, but maybe I just didn't add enough. Thanks for the ideas