Brakes Broken?

No, it is not normal. Why do you think they are worn out? Possibly at 200k but not 20k.

 

It really depends on how the car is driven. There are some around here who have indicated that after 100,000 miles they have only minimal wear on their brake pads.

The Prius attempts to use regenerative braking as much as possible which typically would extend the life of the brake pads significantly. However, if you frequently brake fast or hard, or if you drive long distances down steep hills/mountains (especially without the use of the "B" transmission setting), or if you frequently drive very bumpy roads that cause the activation of the Anti-Lock Braking System, then the brake pads will engage more frequently and wear much faster.

20,000 miles might mean there is something wrong, or it might just mean that your driving environment and habits cause faster brake pad wear than others.

 

Amplifying one of Danny's points: you should use "B" when coming down mountains to avoid riding the brakes. If you drive in mountains but never use "B" that could explain the brake wear.

 

HMMM Just how does riding the brakes wear the pads when they are only used at below 9 MPH and in panic stops? Riding only increases regeneration. I find on most long downhills just letting up on the gas is enough to keep me at desired speed. OP is from San Francisco and there are not any really long downhills near by that would justify using "B".

I think some dealer is trying to sell her a brake jobthat she does not need.

 

I agree with SEASALSA the dealer is in a money making mode. However I have a friend that I have attempted to break of driving with the left foot hovering over the brake pedal. This person is absolutely certain they are doing no braking but I have driven behind them and watched the brake light go on and off even while they accelerate. Although in the Prius that should only cut into the gas mileage?? They also complain about their mileage and are unhappy with their Prius.

 

In reverse order:
May be, but we can't assume that.
Mount Hamilton is near SF and provides an outstanding example of the danger of riding the brakes and the need for "B".
If the braking effort required exceeds what the regen system can handle, regardless of speed the friction brakes will be used. There's no other place for the energy to go.

 

Sheesh. What MPGs do they report? Try to convince them to keep their left floor firmly on the damn floor for a week and see if their MPGs improve. This experiment will be less expensive than selling the Prius and buying something else.

 

OP specifically states:

Perhaps. Perhaps not. Without seeing and measuring the brake pads it is difficult to say for certain.

 

Take it back to Toyota! Evidently they did not fix the original problem. I have 70K on the original pads with less than 10% wear. Many have gone 100k+ before replacing pads.

 

Ah, *now* the whole story comes out! The "event" repair was almost certainly done incorrectly. Take it back to a dealer, maybe a different dealer, and have them fix everything right. (If you like anecdotes, after 26K the wear on my pads is negligible.)

 

If I had to bet $1, and for lack of better terminology, I would guess your regenerative braking isn't regenerating. I could be wrong, but hey I'm only betting $1. Do you get a slight whirring noise as you slow down past about 10mph or so? After some city driving does your screen show that you've recovered any energy from braking?

 

Are you putting your car in neutral?

 

A sticky caliper will cause increased brake pad wear, although wearing them out in 20k seems extreme. Improperly lubricated pins mean the caliper cannot slide back and forth smoothly, causing it to "stick" in position after the brakes are applied with the pads still in slight contact with the rotor.

 

I definitely recommend another trip to a Different dealer for a recheck as to why your pads are wearing. The dealer I work at sells more Priuses than almost anyone except for a few in California. I have NEVER done a set of Prius brakes. Ever.