LLyod - one thing that we found is that there are 2 types of D44 variants being used on the Xs. The first type released was a 2 spider rear end. This is probably what you and I have in the rears. The 2 spider axle blew out after 150 miles of racing.

We originally had a 4 spider gear that went a full 600 miles of testing / racing... then it too went bye bye. Then the one I just mentioned. We were then given a 4 spider gear rear and it lasted the whole 250 miles. I appears to be that the early 2nd Gens had the 2 spider gear.

If you feel comfortable opening up the rear dif cover it would be interesting to confirm if you in fact have the 2 version. It is interesting that they quickly learned that lesson and went to the 4 spider.

I think you may have a good arguement if you approach Nissan that way. I believe its all internal, meaning that the whole axle housing and actual axle shafts can be maintained while just replacing the other components.

I would like to have Dave (XterraRacer) post to this thread with some of his observations too.

Sorry that your axle went out... good luck.