it could be a u joint in one of my posts called "clicking noise" somebody replied telling me that they usually start ta squeak before they start to click so it could be a possibility.If it's the front drive shaft you can drive around with it removed if you need to drive your vehicle{that only applies to you if you have 4 wheel drive}."Unfortunately if it's the rear, you'll have to replace it ASAP as it'll go anytime, especially at faster speeds".