Lumminaa chevy won't turn.
Damaged rack and pinion steering, bearing failure in the steering column, ball joint seized, just a few things to check.
Does the steering wheel still turn? If it turns freely I would check the u-joints in the steering shaft. Then ensure they are coupled to the input on the rack and pinion. If those are good then it is most likely rack and pinion itself as tennisshoes has said. You can get access to the steering u-joints if you remove the plastic cover on the inside of the firewall behind the brake pedal. I've had this happen, the front subframe bolts fell out and the suspension separated the sub frame and body enough to dis-connect the steering from the rack's input shaft. Good thing I was only doing 10 mph.
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