I'm going to post two threads because I have two separate issues. Along with many others that I'm dealing with.
I've had this problem in the past. I step on the brakes, usually at higher speeds, and the steering wheel vibrates. It's probably brake rotors. I had the same problem with my Focus. I always wondered why this happens. I do a lot of slow and stop and go driving in urban locations, although I try to be easy on the brakes and don't hit them hard unless it's absolutely necessary. I wondered if that's the issue, or if it's just because of crap, badly made rotors using inferior materials. Or possibly because of frozen calipers. A friend mechanic claims it's because of me braking hard, but I don't brake hard, and he never drives with me so I don't know where he got that idea.
The brake pads themselves are about 1/4" pad left left, I don't know how thick a full pad is but if I have to replace them I will live. The question is, how to prevent this from happening again. Is it because of bad calipers and should I replace the calipers (even though that will add to the cost?). Should I spend $40-50+ on premium rotors which will push total cost quite a bit over $100? With my focus, a year before I got rid of it I had replaced the rotors with AC-Delco's economy/bargain rotors and never had a pulse problem again, so I could try that, but I want to prevent this from happening again.