I have the same van, 125K miles. The brakes started falling apart this past November, Rear cylinder one side, then the other. The master cylinder was next. I did not have ABS codes (until right now!) but have fresh fluid in there now with new master cylinder. I have left the front calipers. I am thinking the hose is a good idea, give it another flush, but if that doesn’t cut it I will change the master as well. Nice job on the free van, mine would sell for $3-4K around here.