Hydroboost issue?

[Johnny Mullet]

Running into an issue here at work with a 2004 Chevy Express 3500 Full sized van with hydroboost. The front brakes will eventually lock up and bring the vehicle to a stop. We had to break the front hoses loose to get it to roll and we got it to the shop and replaced both front hoses, pads, and the calipers compressed just fine.

Van was fine for 3 days and just got a call that all 4 wheels started smoking and all 4 locked up and the van will not move. Going on a tow 30 miles away to get it here but I was wondering if any techs here ran into this situation before?