Is anyone having problem with brake???

I have had a similar experience several times in my 2004 Prius. In some cases when I step on the brake pedal it seems very weak and slows down but doesn't stop with the same intensity as my pressing on the pedal would seem to indicate. I have only had one minor incident where I tapped another car from behind because the car did not stop quickly enough. I am sure that I had plenty of time to stop but the car did not react as I had anticipated.

Other than that the anti-skid system has worked appropriately in wet/slick conditions.

I am taking my Prius in for the brake light and DVD recalls and will have the brakes checked at the same time. Now that it's winter I don't want to get caught with a faulty brake system.

 

WOW! That's an accomplishment! You were made for a Prius. I used to play a game while driving, called "Don't Use The Brakes". I tried to get from location to location without using the brakes, slowling by downshifting, timing, etc. That game helped me fit the Prius driver catagory as well.

 

With every stick-shift car and truck I have ever owned, I have NEVER downshifted to slow the vehicle, except in mountain driving to keep from going too fast.

Why? A clutch job is WAY more money than a brake job. And it's WAY more work too. Ever do a clutch job?

Friend of mine bought a brand-new 1983 F-150 2WD with a 300 I-6 and HD 4 speed trans (Bull low, so really a 3-speed trans). He would always drive me bonkers by downshifting instead of using the brakes. Of course, whenever I drove the truck, I always used the brakes.

In 1985, with only 38,000km on it, the clutch was completely shot. My friend even tried squeezing more life out of it too. So you know what happened: the flywheel was completely toasted. He politely asked me to help him.

My dad had all the tools we needed, and it took me almost an entire day to pull the transmission and take off the flywheel. Around $350 worth of parts if I recall. At that time, front brake pads were around $20 for the complete set.

With my 1992 Honda Prelude, I never downshifted either. Just used the brakes, and front pads in that thing were around $50.

I doubt the pads on our Pruis are that expensive. So I'd much rather replace front pads at half thickness than monkey with downshifting.

 

not very easy to downshift with a single speed tranny

 

I always downshift with my truck, and have 106k on the original brakes and tires. I also don't use the clutch when I shift as was taught how to do this when driving 18 wheelers. I'm also still on the original clutch. As far as I know, I've logged one of the highest MPG figures for the 3/4 ton Dodge/Cummins/manual tranny combo at 23.7mpg. This figure was obtained while driving hilly terrain no less (Decatur, TX to Denver, CO.) I've always been in the practice of looking way ahead, and anticipating what traffic is going to do. It's a necessity when it takes a football field to stop an 80,000 pound projectile at 55 mph.

 

I was refereing to the comment made by tntna. With a regular stick-shift, and especially an automatic trans, you can cause rapid wear of the clutch or the transmission clutchpack/bands by improperly downshifting.

Unless I need to control my speed on a long downhill grade, I never downshift a regular stick-shift or automatic. Of course, there are a huge number of downhill grades here in flatlander country. :roll:

If you're somebody like Wolfman with experience driving heavy trucks, then you already know how to properly downshift a stick shift. I drove a pulp truck one summer while putting myself through college, and it's a lot easier to match RPM when the RoadRanger doesn't have synchronizers. You get a feel for it.

So if your idea of downshifting is to shift your stick-shift into the next lower gear and let out the clutch, letting the clutch absorb the difference, use the brakes. A brake job is way cheaper than putting in a new clutch, or putting new bands in an automatic transmission.

 

As I understand one of the 12 or13 computers in the car clocks the time between when you take your foot off the gas and hit the brake. If this is short it reads this as an emergency stop and goes directly to the friction brakes *and* the regen. I have in the past termed this "dropping the anchor" and several posters agreed (origional Prius forum).

 

On the point of the Prius' four processors, what are their clock speeds? (Mhz, like a desktop computer)

 

<div class='quotetop'>QUOTE(ammiels\";p=\"59393)</div>

The concept is correct, however the method is not. The brake control computer compares the rate of change in brake pedal position and the rate of change in brake pressure. If the rate of pedal travel is very high and the pressure measured is less than near maximum, the "brake assist" feature kicks in, essentially applying the brakes at maximum until pedal travel is reduced. This ensures maximum braking is achieved regardless of leg strength or pedal position (some do not sit such that they can apply the brakes fully). The throttle position sensor is not used in this comparison, as a failure of the sensors could indicate that the throttle is applied and braking is not needed.

 

8) Hi Wolfman !!

Well.... you took me back about 60 years to my '31 Model A 2-door sedan and Double Clutching. Nothing like your 18-wheeler but after a start from dead still I was able to shift gears without wear and tear on the clutch. A skill I haven't had opportunities to use in many years.

As Bob Hope would say: Thanks for the memory....

 

427 corvette; 42,000 miles; original clutch, 2/3 of the brake pads left. double-clutched all the time.

drove a 5-ton truck once, and learned to double-clutch on UPSHIFTS.... it had no synchros in ANY gears.... took about an hour of driving to figure that one out...

double-clutching is easy, and not only saves on clutch plate and flywheel damage or wear, it also saves your synchro cones, too!

worst of all worlds, as most of you know: "holding" your stick shift car on a grade at a stop sign or light by using your gas and clutch. NEVER, never, do that! learn to hold the car with the parking brake if necessary, then get the car moving asap [as smoothly as possible] with as little clutch slipping as possible.

if you're taking more than about one second of clutch slip to get the car moving, you need to practice more. two seconds is nearly unforgivable, and your clutch and flywheel will be the ones that don't forgive you! half a car-length to fully engage the clutch should almost always be enough. and it can be done without giving your passengers whiplash, too!

74,000 miles on my isuzu diesel (60 hp at redline), on the original clutch and synchros (and brakes.) if you downshift right, you can save your brakes to the point of rusting them in place by under-use!

and...... the prius doesn't, imho, have "one gear"; that's misleading. it has "one set of gears". it's just that the rpm of that one gear that outputs torque to the wheels has a very wide range of rpm!

 

how do you double clutch?

 

I am at Direct Toyota in Columbus, Ohio getting my brakes checked now. I've experienced the brakes grabbing and locking up as I slowly come to stops. The problem is that when they do lock up we nearly go through the windshield!
If we didn't have our seatbelts on I believe there would have been cheek marks on the front windshield on both driver and passenger sides.
I wonder if there are adjustments that go awry when the car tries to go into charging the battery. I've noticed it at slower speeds but most noticably coming to a stop. Could there be a link to the mechanism of charging and this problem of out of control lockup at slow speeds?
I've been impressed with its stopping ability (on a dime to speak) but this is an "unexpected", extremely quick braking or stopping not controlled by me. It is an out of control stop since when it happens (as I'm trying to come to a slow gradual stop) it just chooses to stop totally when I'm not ready and is not at all normal.

 

Have you tried going to N prior to a stop or two to see if the rotors are merely rusted a bit? I've seen the technique suggested many times over the years...

N keeps regen out of the equation, forcing the friction brakes to shine up.