Test the CV by driving in a very slow, very tight, turn. With the steering wheel to the tops. If the CV has a lot of wear it will knock. Never heard of swapping them to even the wear. If  they have worn sufficient to knock like that, replace them before they catch ou out in the middle of nowhere on a dark and stormy night!

John Rodgers
"88 GL Driver in New Mexico

Madsen wrote:

I think I am in need of replacing a CV joint. The other day, I was driving to work which takes about 45 minutes. 30 minutes into the drive I came to a stop light and took off normally. A clunking sound eminated from the rear. It got louder and louder and more frequent as I drove faste. I stopped for a minute to inspect underneath. Didn't see anything out of the ordinary, so I thought I would try and get to work by driving it real easy. It still clunked until I hit a nice bump in the road - the noise stopped. Once in a while the noise would re-occur when turning a corner, again it will stop if a bump is hit or if I move the drive shaft back and forth by hand.A mechanic advised me to switch the CV's from one side to the other in order to wear the ball and races differenty.Any tips and tricks from ya all on this????? Thanks, KenOntario, CANADA