I would like to share my mysterious experience here to see if anybody can help me to solve this issue.
According to their recommendation, the whole brake system of my Volvo XC90 was replaced at this workshop. After driving back home, we found the E brake did not function. I sent an email to the workshop and requested to get the problem fixed the following day since we are going to travel afterwards. We sent the car back to the workshop the next day and the E brake was readjusted to fix this problem. In the morning of the third day, we drove about 20 minutes in the city of London and then entered highway 401. After driving about 10 km on the highway, we heard some strange noises and felt the violent vibration and the car was like driving on a very bumpy road. We had to pull over our car. I realized some burning smell coming out from the right rear wheel. I attempted to use my finger to touch the right rear disc and found it was super hot to burn my finger. However, the other three discs are just gently warm and I can put my fingers on them without any un-comfortability. I called Volvo London and talked with the lady named Ruth. After I described the problem to her and reminded her that my car's brakes were just replaced. She definitely said that something got stuck on my car's rear right wheel and it was nothing related to the car's brakes. I told her that my car's brakes were just replaced at your workshop. She said "it is nice". I have to say she was very rude this time even though she sometimes behaves ok. I am just curious should the so called service advisor behave in this way when the customer desperately needs help? Then I requested to talk with the service department manager. I described the problem to him and he confirmed that this phenomenon was not normal. He suggested me to call roadside assistance to get my car back to the workshop. After my car was towed back, I also talked with the service manager in person and he confirmed again that the phenomenon I described was not normal. They promised me to check it and sent me back home. In the late afternoon, they sent my car back home and an invoice report as well. Mysteriously, they did not report anything wrong. I have communicated with Volvo Canada and they confirmed all the parts consumed on my car are certified to defect free. Then the question is: what caused the malfunction of my car's brakes on highway? I could not get any reasonable explanation from the workshop. Who can help me to explain what happened?