[casper sc/1ss/rs]

i broke my right rear axel on my vortech supercharged 2011 camaro ss at the drag stip friday. i didnt even take it to the dealer because i knew what they would say and i was worried they would fix it and then hit me with a big bill so i ordered the axel from my local dealer and fixed it myself but now there is a little vibration at higher rpms when i let off of the gas and the motor is holding it back i beleive the axel is not exactly right what do i do? all the dealer will do is tell me to bring it in and they will look at it. has anyone had this problem with a replacement gm axel? the vibration is not bad but its there and its agervating do i need to order another axel or what? please help thanks!!