Brake Disc Caliper problems of the 2006 Dodge Grand Caravan

Our brakes have failed for the second time. I took my van back to the shop that replaced the pads and rotors in may. They told me the calipers were defective, as they were under warranty I took the van to the dealer. The dealer stated the new rotors that were put on in may were defective, they refused repairs and charged me $50.

Brakes constantly squeak and rotors have uneven wear. Told by dealer when I took it in that brakes were fine and still had a long life this was at 12,600miles. At 20,000 miles problem worst and now more than one year with vehicle told it need new pads and a left(passenger) caliper. Total cost $396 plus tax. They would not repair under warranty, had expired. I replace the caliper on my own and new pads. Now at 36,000 miles same problem on drivers front side needs new pads and stuck right caliper. I brought this problem up to the dealer again and was told it was a bad driving habit causing this. Both times told fix it on my own or pay us(dealer) to fix it. I think this is a defect in the vehicles braking system, yet the dealer will not give me a written estimate unless I have them do the work. Something smells!!!!!.