Help-Car sounds like a diesel!!

[09YG]

My car sounds like it is a diesel. When I’m in drive, and I apply my breaks, the car makes a loud vibrating sound, as if it was a diesel. This only happens when I am in drive. If I am in park, neutral, or in reverse and I apply my breaks, no sound is made. What is wrong with my car?
Details- 09Yaris Sedan- Automatic- Apx 80k KM

[nookandcrannycar]

Originally Posted by 09YG

My car sounds like it is a diesel. When I’m in drive, and I apply my breaks, the car makes a loud vibrating sound, as if it was a diesel. This only happens when I am in drive. If I am in park, neutral, or in reverse and I apply my breaks, no sound is made. What is wrong with my car?
Details- 09Yaris Sedan- Automatic- Apx 80k KM

If you are driving with the flow of traffic on a highway (non commute time) and put the car in neutral and put on the brakes (don't do this if you can see a car behind you in your lane ) does this happen? If so, my first though would be warped front brake rotors. I suggested the test because you are unlikely to be able to repeat what you describe (IF the issue really is the rotors) in neutral if you are going very slowly (perking lot, etc.). I am also assuming you are going slower than 'highway speed' in reverse . I have had what you describe happen on a car heavier than a Yaris and the issue was warped rotors. The really well informed pros on this site might have a less pedestrian, but potentially more accurate suggestion.