When i brake completely when im at a red light my 2007 prius makes a knocking sound...

Not sure if this will help but do some aggressive braking in neutral to clean pads and shoes off. I had to do 5-10 stops before mine felt and sounded better.

 

as you are coming to a stop or after you have stopped?

 

Is it just as you're close to reaching a stop? Mine does that too. I think it has to do with the digital control of the wheel brakes. As we near a complete stop, those of us seeking a jolt-free experience will release brake pressure as we near a complete stop to reduce the rebound jolt.

Since the wheel brakes are computer controlled, I believe they operate at digital levels instead of the completely smooth, analog brake application of a traditional hydraulic system being controlled directly by the pedal.

So as we modulate the brake pedal, the wheel brakes are experiencing distinct, digital pressure changes from level 5 to 4 to 3, for example. The change to each digital braking level can be slightly heard and felt through the brakes and chassis.

It's completely normal--it's just a characteristic of the digital brake control.

 

sounds are strange, i get this choo choo train sound coming from the front but it turns out just brake dust in the rear drums, a shop charges $10 to clean them out while giving me free inspection, they tell me how many mm are on the front and rears, I then tell them they're the original pads (front) and shoes (rear) and I watch their astonishment.

if you are smart you will use regenerative braking, but this non use of the conventional brakes means there will be rust accumulation that needs to be cleaned off with a couple slams of the brakes once a month or so.

I am curious why others are saying to put the car in neutral, I was always under the impression that very light braking will use the regen system but any aggressive braking will use the normal braking, so slamming the brakes should be enough to clean off the rotors w/o having to put the car in neutral, so why do it?

 

Putting the car in neutral and coming to a long, gradual stop is the best way to polish any oxidation off of the wheel brake friction surfaces as the car uses only the wheel brakes when in N.

Slamming on the brakes not only causes needless wear/tear and could be dangerous if someone just pulled in behind you, but it doesn't guarantee the regen brakes will kick out (regen does most of the work for even moderately-aggressive stops) and likely won't polish the wheel brakes very well. It's like trying to polish the hood of your car by leaping onto it with sandpaper on your shoes as opposed to 20 minutes of gentle circular motions with a shammy.