I always try to troubleshoot on the KISS principal. Check the simplest things first and work towards the more difficult. By that approach, I would:
1. Check lug nuts - are they all present and tight?
2. Check air pressure in tires - all to factory standards and equal between tires?
3. Check tire treads - anything funny there (uneven wear, broken belts, bulges)?
4. Get on your hands and knees in front of the VX & inspect your CV boots - if one is torn, you'll have grease splatter all over the place.
5. Jack up front end & shake each front wheel top to bottom - any play?
That's the easy stuff - now onto the more difficult/messy:
6. Check fluid level in front differential.
7. Check fluid level in transfer case.
8. Check fluid level in transmission.
9. Trace your exhaust pipe all the way from manifold to tailpipe focusing on the heat shields. If any are loose, they'll rattle against undercarriage components.
10. Remove wheels and check brakes for trapped gravel in the brake dust shields.
That's a start & if no problems are found, then let us know & maybe we can think of something else to check. Good luck & have fun wrenchin!