Hope someone can give me some guidance here...1997 Wrangler Sport 4.0 w/ 171k...I've noticed a grinding noise coming from the front passenger side.  At first I thought it was a brake issue but those are fine.  I took the tire off and it seem to be coming from the inner axle (?... boy I wish I took auto mechanics instead of wood shop!). The noise seems to be worse when the wheel is turned to the left and it's definitely rhymic meaning it happens in the same spot as the wheel rotates.

Any thoughts anyone?

Rocky  

If the noise happens when the steering is perfectly straight, it is the unit bearing (hub assembly). If it makes the noise only with the steering is turned, it is the u-joint on the axle. Unit bearings cost around $100 and needs to be removed in order to pull the axle out to replace the u-joint. Unit bearings wear out often and you might consider doing both at the same time. U-joints cost $15. The whole job takes an hour, per side and depending on how good you are at replacing u-joints, is pretty easy. Some people have a hard time pressing the u-joint caps off, but you can do it with a vise and an appropiate size socket.  

Thanks for the reply.  I'm going to guess that if I have my mechanic do this it'll be roughly $200.  Does that sound right?  Just don't have the time to do it myself or probably the skill to do it either!

Rocky.  

The parts from the mechanic usually cost more because they make a profit on them, but they also guarantee them. So probably $175 for parts if you did both the unit bearing and the u-joint and 1 to 1.5 hours labor at $75 to $90 per hour. If you did the unit bearing at the same time it would be like a free install. If you did just the u-joint, probably $150 to $200 total.