Durango LTD HEMI

• Automatic transmission
• 53,438 miles

I had just changed lanes and the traffic was stopped ahead about 150 feet. I applied light pressure to the brakes and nothing happened, it felt like the brake pedal was attached to nothing. I stepped on it again and nothing, I looked down quickly to make sure I was stepping on the brake, then I quickly hit it 2 more time then pressed with both feet and there was still no pressure under the pedal... then I struck the vehicle in front of me. When my truck hit the vehicle I felt the brake pedal jar and then there was pressure, the brakes engaged. They worked so I could limp to the dealership. Thankfully I was only going about 30 km/h so no one was hurt, however it is an awful feeling. After sitting at the dealership for 4 days, they called to say that they "drove it around for awhile and the brakes are fine". I went in and said "so you took stuff apart, checked the brakes" and they said "no". I had to freak out to get them to agree that they should do that! I said I was not driving it on the highway with my daughter in the truck until they could assure me it was fixed. Has anyone else experienced anything like this?