Axle or transmission. You tell me.

[Jazjnky]

I recently had the axles changed in my 2002 X5. I have 74,000 miles on the car and have had no problems except a window regulator that was changed. Last week the car would not go in to gear so I went down and pushed it into a stall. After a few minutes, the car just worked. I took it to the dealer the next day and they could not duplicate the issue(of course) and there were no codes to report on. They said "must have been a glitch in the switch, drive it as it it seems okay to us." so i am driving the car on Saturday morning, about 70 MPH and I feel and hear a noise like I have a flat on the front left side of the car. The engine is running with no problems, but the car will not engage. I coast off of the freeway and in to a parking lot. The car runs well, and I can hear the tranny as it shifts in to drive or reverse, but no go. Did the axle let go and it's just spinning , disconnected, in there? or is it my tranny and i now have to but another Mini Cooper?