Steering Column Repair: steering column (lock), steering column lock, arm bushings

Question
Hello,
I can not lock my steering wheel, also not sure but every now and then i have a little knocking noise is this because of the wheel not locking, I did replace the upper a-arm bushings, but still hear the noise? So my next thing to do would be check why the wheel is not locking could this be the problem.? The truck is a chevy 2004 four wheel drive, 2500 HD Any input would be helpful
Thank You, Tim

Answer
Hi Tim:
The locking mechanism is a small pin in the steering column just below the steering wheel.  I doubt very much that it would cause a knocking noise.  You mention the A-Arm bushings.  Those are located under the hood near the wheel and are part of the upper suspension.  I say this because they are quite a distance from the steering column.  There is actually have no relationship between the two.  
Did the steering ever lock?  Some of the newer trucks (like yours) don't even have that mechanism in it, and I don't have any way of checking to see if your is one of them.

I know it's not a lot of information, but diagnosing a symptom like this on the internet is very difficult (at best).  I have tried before to answer noise questions on the web and it is just too difficult. Your clicking is my ticking and your knocking is my thumping, etc. I would suggest going to a couple of shops and have them just drive it with you to get an idea of what you are after. If they want you to leave it for diagnosis, find another shop. The good shops will be glad to 'go for a ride' to help you before getting involved. If after you do that you wish to ask me about their opinion, I would be glad to assist you with that.
Good Luck
Doug