I have driven two similarly aged chevy trucks ('04, '05) and both have a very sensitive steering feeling. Small bumps in the road, especially going around corners seem to rattle the steering wheel and even produce a knocking noise in time with the bumps. I find this strange since you figure a truck’s steering components to be heavier-built. Could the tie-rods be loose? For such new vehicles I would expect flawless performance.
Its the dreaded “half-shaft” steering shaft. Has been a known by GM for about 8 years. The only fix i know is to have the half-shaft knuckle re-greased. Call a GM service dealer and see if there is a permanent fix by now. And,yes,I’ve had it re-greased twice already on my’04,Sierra.
I had a 2000 Cavalier and the intermediate steering shaft was replaced at around 36K for similar issues. It started acting up again around 100K. Dealer said replacing was no longer possible - GM won’t sell the shaft unless it is damaged and has to be replaced. My car’s symptoms did not dictate replacement. They insisted the car was safe. They also said that re-lubricating would probably not help. Of course my car was several years older than yours.