steering

Hey all,

I have another one for you. Whenever I turn the steering wheel all the way to the right or left, when it is turned to the max position and accelerate, there is this awful clanking/grinding noise. It almost sounds like something is going to pop off or crack down near the front tires. Also, when I accelerate, the car starts to studder, like it is going to stall. This has happened since I bought the thing but I never thought anything of it as I figured it was normal. But the more I hear it the more it worries me. Any ideas?

Thanks.

Steering stops need grease...
http://mywebpages.comcast.net/xterra/tech/steeringstop.jpg

4 total, one on the front and rear of each lower control arm.