Recently on my drive home to VA from PA, the front passenger side of my car started to vibrate violently. I pulled over to the side and thought I might have a flat, but nope the pressure was at 32psi. I thought it was my lug nuts, so I took off the wheel, looked around in the wheel well, inspected the axel (still solidly connected), axel nut (still on tight) and all of the ball joints (only 2 months old and still tight), retightened the lugs nuts, wiggled the wheel from left to right and up and down and it had no wheel bearing or ball joint play (brand new front wheel bearings), than drove off carefully.
I slowly upped my speed and going into each gear carefully with no vibration happening. I left off the gas and it started vibrating violently again. I noticed how it only did this when i was above 50mph, coasting without the gas pushed in and the clutch pedal not pressed in. If I push in the clutch while coasting it wont shake, neither does accelerating quickly.
I talked to a friend who said it could either be my axel or the LSD.
The Y1 tranny has been rebuilt with gear-speed carbon coated syncros, but with the same old OEM LSD. I am going to have someone locally to check it out, but I just want to hear from others if they know what the problem could possibly be.
Some one help me please!

 

CV joint would be my wild stab at it.

 

Thanks, I will definetly take a better look at my axel and everything this weekend. I really hope its just an axel, so it can be cheaper to replace than my diff

 

bump for anyone else's input