The noise is worse when under load, such as going up a hill, but it also makes noise just cruising down the street, like the front end is going to rattle apart. I haven't tried 4WD on the pavement yet, so I don't know if that makes a difference. From my understanding of how the 4WD works on the XUV, it only engages if the rear wheels are slipping, so it may not make a difference, but I will try.
If you don't already have the noise, I doubt if you will get it. This seems to be a problem that starts from day 1, not something that gets worse over time.
My recommendation for XUV shoppers is to drive the actual unit you are interested in on pavement before you buy. I tried mine on dirt and did not hear anything, but when they delivered it, and I drove it up the driveway, the noise was there at full volume.