Hi Stephen
When you say it didn't last very long what do you mean.
If it fails it is usually that the circlip has not been fitted correctly.
Try rebuilding it using the guide on the Durango website.
http://www.team-durango.com/blog/201...ild-guide-pt1/
I have run my car at about 6 race meetings now with rc Lazy diff balls. And i have found it to be the best ball differential i have had in any car ever and i have been racing for over 25 years.
Let us know how you get on.
Paul