Poll: Are Prius brakes a problem?

[bwilson4web]

Hi,

The question about Prius braking has occupied 2-3 threads with variable degrees of opinions and little or no metrics. This poll is to count, to get a metric, of who and how many have any experience with it. This is not to change impressions but just to measure how the community sees the problem.

Please, only those who have or have owned a Prius should vote. It is an open poll. Pick either "no experience" or two answers for either the 2010 or 2004-09 Prius.

I picked "no experience" for our 2010 Prius because I've only seen something like it once and I had to steer for a pot hole. This is less than once per month, in fact, only once since May 27, 2009. I can't complain about something that isn't happening in my observation.

Those who think it is a big problem could help by posting photos of the roadway where they experience the problem. Photos make is possible to possibly replicate but right now, I just can't replicate their experience. You'll have to help us.

Thanks,
Bob Wilson

[emPG]

There is major street repair being done on my route to and from work and almost everywhere I go. It has been totally torn up and repaired but there are some major bumps and a huge pothole. When I hit the pothole that is when I experience what I call the weird feeling which I guess is the brake/traction. It does not seem to make me lurch ahead or make it take longer to brake. It just "feels" strange. It only happens when I am going in one direction and this is the only place it happens. It really is a huge hole in what is not even a piece of paved street. I can't wait for them to fix it and then I am sure that they slight change I feel will go away. I find the brakes on my Prius to be the best brakes I have ever had in a car. When I need them they are there and they are firm and stop the car without any sway whatsoever. and they are fast. I am delighted with my Prius and do not regret my purchase. It was bought in late Sept, but I am not sure of the manufacture date. I will say that my cargo net was correctly installed so it had to have been made after that issue was discovered and corrected.

Thanks for the poll- Great idea.

[ibmindless]

It took me 2 1/2 years to experience the problem. I've encountered it about twice since then - over a 5 month period. It is definitely a scary experience the first time. I'm on the fence as to whether it's a safety issue or not. In my situation, I've only encountered it during speeds under 35 MPH and not with a critical consequence looming.

Regardless, brakes shouldn't stop braking when you're applying the brake pedal.

[dogfriend]

I have a place where I could consistently make it happen that is right around the corner from where I live. Now that I have replaced the OEM tires, it isn't consistent anymore. In any event, it is no big deal and I think it is just a quirk of the Prius brake system.

[DetPrius]

I chose scary, safety issue but I wish there was a scary, _potential_ safety issue option. I've read the thread and for me it comes down to what ibmindless said. Brakes should keep braking, period, even during transition from regen to friction.

Bob, there is a rough patch near my home where I was able to recreate it when I tried last week. I may go over there tomorrow with a camera and then try it repeatedly and see how many times it happens out of 5 or 10 tries.

I agree with an earlier poster that it should be investigated, and it may be determined that it does not increase braking distance, and if that is the case AND there is no way to get rid of that loss of braking sensation, so be it.

Again, I want the Prius to be wildly successful but this issue can only hurt Toyota, the Prius, and hybrids in general.

I read some posts where the driver was unsure if they had experienced this. If you are unsure if you have experienced this issue, there is no question that you have not. You will know it when it happens!

[TonyPSchaefer]

In my opinion, most of the people complaining about this are those who practice "free-fall breaking" in which they wait until the last second to break and pray nothing goes wrong. Most who coast to stops (or coast to avoid stopping) and break long and slowly rarely encounter it.

[DeadPhish]

Originally Posted by TonyPSchaefer

In my opinion, most of the people complaining about this are those who practice "free-fall breaking" in which they wait until the last second to break and pray nothing goes wrong. Most who coast to stops (or coast to avoid stopping) and break long and slowly rarely encounter it.

This^^^^

This is probably why I've never experienced anything like this sensation in 4 yrs and 139,000 miles of driving my '05. I never brake hard at the last minute unless there's an immediate hazard and then the brakes are the best I've ever experienced.

I coast to a stop almost all the time and try to time the lights and traffic as a game ( I've always done that for 40+ yrs of driving ). Most of my driving is suburban and rural highways so there isn't much need for constant stopping as a general rule. But I've spent enough time in Boston, NYC, Phila, DC, Norfolk, Richmond and the traffic corridors of I95 to be well aware of heavy stop and go traffic. But I've also spent most of my business life in those very corridors so I also know what to expect.

[spiderman]

Originally Posted by TonyPSchaefer

in which they wait until the last second to break and pray nothing goes wrong. Most who coast to stops (or coast to avoid stopping) and break long and slowly rarely encounter it.

I would have to agree with this as I have never felt the sensation either (5,000 miles) and I avoid the quick braking. I will be prepare though, that is for sure.

I have had the reverse, grabby thing once.

[risingsun]

Originally Posted by TonyPSchaefer

In my opinion, most of the people complaining about this are those who practice "free-fall breaking" in which they wait until the last second to break and pray nothing goes wrong. Most who coast to stops (or coast to avoid stopping) and break long and slowly rarely encounter it.

Yes, I fully admit the one time I know I felt it, I was driving by myself (which often tends to have me driving a bit more aggressively) and I was speeding into a stop sign a bit quicker than typically, and I hit a bump where there was a pavement seam/match. It was dry - no wet pavement or anything. I have driven this bump many, many other times in a less aggressive fashion and felt nothing. And what I did feel went away quickly with a bit harder press on the pedal. If you know what can occur, and how to react to it, the panic-inducing surprise will be much less of an issue, or even non-existant.

[cwerdna]

The poll was a little confusing to me and I wasn't sure how to answer so I picked:
2004-09 Prius - about once per week
2004-09 Prius - no big deal, not a risk

It's tough for me to say as I alternate between my Prius and my Z and now my commute is real short so the frequency is probably between once a week and once a month.

When I worked in Sunnyvale, CA, if I were to drive my Prius every weekday, I can trigger the skid light almost consistently at one spot and if I were to brake there, I'd hit the "issue" for sure.

I can't provide pictures of the roadway anymore but the spot is at san aleso and n mathilda ave, sunnyvale, ca - Google Maps.

To repro, get off of 101 and go southbound on N Mathilda Ave in the rightmost lane closest to "Mo Sys" before San Aleso Ave. You should hit it just slightly before the traffic light at that intersection.

edit: It's likely due to this broken/cruddy pavement at http://maps.google.com/maps?f=q&sour...,0.004292&z=19 (thanks to Google street vew). I'm usually in that rightmost lane in order to turn right into Mo Sys (even though I want to go left) due crap left turn traffic light timings.