This may be a stupid question. Sorry if it is. When I am backing up my 1996 range rover, and turning at the same time, there is a growling noise in the front end. The 4 wheel drives I have had previously had u-joints in the front axles, which had a distinct clunking noise when they went bad. I am not familiar with the rover axles yet. Is this noise I am hearing normal, or something I should be concerned with?