I dont think the dealer would be able to electronically adjust the steering rack. We have a GM Tech2 scanner and have never seen this option. When they say its adjustable they mean as a software package.
That being said....I have a 2001 DTS that should be using the same steering rack. When I got that car it did have a fairly loose feel. What you can do is tighten up the preload on the rack. I think the spec is
45-90 degress on the preload. Mine was set at about 90 degrees...now it is set at the tighter spec of about 45 degrees. The preload is on the rack under the car.
Logan Diagnostic
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