Sometimes inner CV joints have issues and cause vibrations. These can be very hard to track down. The symptoms usually occur driving at speed, say 65 to 70 mph, and sometimes as low as 55 mph (but not often at that speed). You might notice that if you turn the wheel slightly to one side or the other, the vibration gets worse (or better if it's an inner CV joint problem). Once you turn the wheel straight again, everything’s fine. This normally tips me off to an inner CV joint problem.

Finding out which side it’s on gets a little tricky; I'll admit that it's mostly a guessing game. You can push up on the axle near the inner CV joint to check for play. The side that has the most play is likely to be the bad CV joint. However, this is not always the case. You can't repair these; you need to replace them. I'd recommend replacing the entire axle before attempting to replace just the inner joint. Axles, for the most part, are inexpensive these days, and replacing just the inner joint, if you can even find one, just isn't practical. If you replace one side and your vibration is still there, replace the other side and recheck. I did say this turns into a guessing game; I wasn't kidding.