intermittent rear vibration at 60mph

[djvx]

Yes, check your rear diff fluid (both level & for metal shavings). It may be as simple as low level.

Remember though that gear oil smells pretty bad even when new. Don't mistake that smell for burnt fluid.

If it doesn't "leak out" (i haven't ever seen any leaks ) could it still be low?

[tom4bren]

Yah, you can usually spot leaks ... but not always. If the leak is out by the wheel, the oil may get blown away before you'd notice. Murphy's law does apply to the VX.

Remember a sage piece of advice though: ALWAYS remove the fill plug first, NEVER the drain plug first - just in case you can't get the fill plug out. Ya can't drive with an empty differential. IIRC, credit goes to etlsport for that one.

[SilverBullet75]

If you are lifted too high, you will get that grinding. I was using OME 919s plus DAYSTAR spacers and it was really bad. Removed the spacers and it was manageable by greasing the driveshaft. Try greasing first. It helps.

[VXorado]

Try greasing first. It helps.

+1, I was getting a grinding noise from the driveshaft u joints until I started greasing them regularly. I would only get the vibration/noise at highway speed, so it seems to fit the problem.

[Y33TREKker]

...greasing the driveshaft. Try greasing first. It helps.

X2