j30 diff question

[civilized_drifter]

so i put a j30 diff in my car about a year and a half ago and its starting to vibrate a lot in 5th gear and when i let off the gas it knocks. first i thought it was the drive shaft but to my dismay there is a little bit of play on the driver side input shaft on the diff. i am just wondering if there is any way to fix it or just to replace the whole diff. thanks

[let5l1de]

if you developed play in the rear diff, something must have severely worn and possibly metal shavings may have navigated throughout the whole rear diff. This will take some time and money to rebuild.

It's much easier just to replace the rear diff with another used unit.

fyi: j30 may have a 3.916:1 ratio ring & pinion. the 240sx is 4.083:1

~m