Steering Column Repair: Steering problem, gmc yukon, intermediate shaft

Question
I have a 2001 GMC Yukon with just over 112,000 miles.  Of late, when turning the wheels hard to the left (shows up the most when, for example leaving the parking garage) there is a catch or grab in somewhere.  The first time it did this, it felt almost like I had run the right front wheel up against something.  When I turn harder it will 'pop' and continue to turn normally.  The slower I am traveling, the harder the catch is to pop.  It doesn't do this turning the wheels hard to the right.  The transmission was serviced 20,000 miles ago and inspected 5,000 miles ago, and the rear brakes replaced at that time.  About a year and a half ago, I was hit on the left front wheel well, but supposedly there was no damage to the axle.

Answer
I have to apologize for the slight delay in my response. I went to post this for you but our server was temporarily down for backup.

More than likely what you are describing is a problem with the intermediate steering shaft between the column and steering box. This is a very common problem with the GM Truck (ie. Silverado, Tahoe, Yukon, etc) in that era. GM does have a technical service bulletin on it, but only requires greasing the shaft. You may be able to remove the intermediate shaft and pack it with grease yourself. This may cure the problem temporarily. How long is anyones guess. I've seen them work fine for years and then I've seen some last only a few months (until the grease is displaced). The long term cure is to replace the intermediate shaft.

Hope that helps.
Have a great day!
-Jay