I have a completely stock 2004 Excursion 6.0 with 211k miles. The other day i was driving and heard a whine that sounded like a faint power steering pump whine. I turned into the driveway and all of a sudden the brake pedal started to vibrate, was doing this without pushing the brakes. The next day the whine got really loud at times and got really loud when i accelerated hard. Havent had much of the vibrating pedal anymore. Any ideas on what issue is, and what the cost will be?

 

Have you checked the power steering fluid? If your leaking it will effect the brakes on your diesel.