grinding noise/vibration when turning

[Blairs97Hoe]

I have a 97 Tahoe 4x4. It has recently started making an awful grinding type of noise when turning the wheel (either direction) at a slow speed. Parking, drive thru's, etc. It does not do this when you first get in it but after driving it a good 30 minutes or so. Whe you first get in it, its smooth as butter. It actually causes the steering wheel to jump or vibrate I guess you could say.

Also while Im here, just out of curiosity...the truck also has a habit of vibrating badly once I hit about 70mph on the interstate. Anywhere up to 70 and 75-80 is normal amount(or at least normal for my truck) but right around 70 is awful.

Thanks in advance.

 

[SunlitComet]

This could be a brake or steering. You can start by checking the run-out on condition of your rotors and other brake components. For steering it would be advisable to raise the front end, grab the tires and turn them side to side while some one inspects for loose parts. If you have eliminated worn front and parts or tires assemblies you may be running into a problem with the steering pump or gear but more specifically the power steering control valve and the steering angle sensor on the steering shaft. It is designed to adjust the stiffness at different speed. Variable speed steering effort. It is not uncommon that when the steering sensor goes bad the steering may act like it wants to go some where else.

 

[Daytony]

Something that happend to me before and worth checking, If you have push button 4x4 check to make sure its in 2wd.

 

[07Burb]

Looks like sunlit has ya covered as that's what I was going to post so 'x2' on sunlit's advice...

 

[gpracer1]

It could also just be a low level of power steering fluid in the reservoir. I would check the simple stuff first.
I have replaced my steering sensor due to the steering taking more effort than normal when making an arc turn like a mellow curve in the road, then suddenly you would get full power steering and it would cause you to "overturn" the wheel. It was almost dangerous.

 

[SunlitComet]

Something that happend to me before and worth checking, If you have push button 4x4 check to make sure its in 2wd.

4x4 system does an automatic fallback to 2wd at each ignition on cycle.

 

[Donnie Yukonie]

what about a hub?