Wrong tires on my car

I went to the sears auto department to purchase some tires for my Lexus. I told the I wanted the recommended tire for my car. I told them the tire size and speed rating. The tire speed rating is 92V or 92H. They put 94H on my car and the car has a vibration when I reach the speed of 60 or better. I took the car back to the sears store at Southlake Mall in Marrow, Ga. I talked with the manager about the situation and he told me that the 92 did not make a difference only the letter after the number. I told him I specifically requested the 92H to be put on my car and he refused to change the tires. I don't want the tires that are on my car, I purchased the 92H and that is what I want on my car. He told me he wanted to balance the tires and that will solve the problem. That is not what I wanted from them. I will not be purchasing anymore tires from Sears again after this experience. I want to call and talk with the general manager of sears and I cannot find a phone number or a listing to chat with a manager.

The manager of the store tried to convince me that you cannot compare old cars with new cars that it does not make a difference what type of tire you put on them, it will still be the same in the ride. I told him, I don't care about old cars or new cars, I want the tires on I asked for and the tires I purchased. He still did not change the tires as of this day. Who ever the general manager is I would like to talk with him or her about this situation on the phone or at the store location in Morrow, GA.