U-joints are on the drive shafts, and there are 2 on each one. You would probably hear a clicking type noise more than a grinding noise. Or if they are real bad you would have a bang every time you pushed the accelerator. I had one of my front drive shaft U-joints go out.

CV joints or constant velocity joints are on your front shafts that go to your front tires (if you have 4wd) and have a rubber boot on both sides. Those would make a noise, but usually only when you turn.

Just get under the truck and try to turn the drive shafts by hand. And look for a joint at the front and the back of the shaft to see if there is any play in them. If you can see any play they are bad. Don't get them from Nissan, they are like 70 bucks a piece autozone they are 8 bucks a piece.

 

so no CV joints on 2WD'S CORRECT? There is a part with a boot under there, is it the same thing?

 

should the U joints have any type of fluid leakage? looks like some type of oil is seaping out but nothing major. is this normal? Its not loose BTW. I believe the steering or tie rod has some sort of a boot. Tried pulling on both sides and its NOT loose.

 

No the stock U-joints have should not have any signs of leakage. You must be looking at the wrong thing, take a pic of what you are looking at and then I could help you better. Don't pull the shaft, try to turn the shaft back and forth while looking at the u-joint.

 

This is what a U-joint looks like, I just pulled this pic off the internet, it is not my truck. BTW this one is shot, and needs replaced bad.

 

My 2004 Titan's front driveshaft just about came apart on me at 63k miles. Thanks to this forum I diagnosed the problem and fixed it myself. I posted the project to YouTube if anyone needs step by step instructions... 2004 Nissan Titan Front Driveshaft U-joint Replacement - YouTube.