Fuel Injector problems of the 1997 Chevrolet C/k Pickups

I am very disappointed in this vehicle. The dealership has been wonderful about fixing the differential problem-replacement of ring and pinion and reset depth. The ongoing problem with the steering is frightening. It is unpredictable. Especially while driving in the mountains it may act up, causing erratic steering and feeling like the steering is locking up and completely failing. It has been reported to gm, but they say they have never had complaint, and that they would contact the dealership and call me back. I have found many, many reported situations with steering failure to your organization for the 1997 Chevrolet truck. Now I wonder what gm will due about it. I do not feel I should have to pay for a manufacturing failure of equipment. This vehicle has had fuel injector problems, and has cost me over $500. The rear differential has been rebuilt 4 times and now needs it again. One week after purchase of this vehicle the differential howl started. The dealer said to drive it for 5000 or more miles and bring it in if it still had the problem.