Wet brakes grabbing

I have not run into this at work. No warning lights on? Braking ok the rest of the time? Nothing else unusual? :roll:

 

By “cold†do you mean below freezing?
By “wet†do you mean you just drove through standing water?

Wet brakes can cause a grabbing sensation until the rotor and pads are dry. After washing my Prius, I drive around the block and apply the brakes to dry them off. The Prius brakes are very grabby when wet from my car washes! Unfortunately since we have regenerative braking, this method of drying the brakes is not as easy as with standard brake systems, because the Prius mechanical brakes only engage at low speeds . . . so it takes more applications to heat the brakes in order to dry them.

If you got your brakes wet and then the weather turned freezing, you may have had ice on the brakes . . . even more dangerous . . . and difficult to fix.

 

I have the exact issue you are talking about here.

Sometimes, it even "pops" in reverse when I start it in the morning (like i'm running over a small rock or something).

Anyway, my brakes grab in cold/wet weather, as you mention, and I was debating bringing it in. I actually think they don't always needs cold wet weather, but it hasn't happened in a couple of weeks.

I'm in a 2004 with 18k miles on it and the grabbing didn't start until about 4months ago.

-r

 

Dido, I washed my car Friday then it rained Saturday. During the rain, it would do the exact same thing. At about 6mph it would just "grab" and stop too abruptly. I thought I must have left soap on the front disc brakes or something.

 

From what has been described, I wonder if it really is the pad material grabbing on the rotor? Or if it isn't the caliper itself actually sticking on the slide rails. This car has full floating caliper, right?

It's really important to take the caliper off once a year and clean/lubricate the slide points. I do it twice a year - every fall and every spring - but we have a lot of road salt to deal with here.

 

My brakes started grabbing after I coasted down a long hill on a rainy day about 6 months ago. Now they grab always when it rains.

 

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If by "wet" you mean damp and not saturated, I think most disk brake systems make noise when wet. They also can be grabby if damp. My 2000 GMC Sierra had four wheel disk brakes, and the only time they semed to work well was when the pads were damp, say after I washed it.

 

Since the disk brakes in a conventional vehicle like a Camry are used all the time while braking, they generate more heat and dry off faster. Good point.

 

Your first post nad6211, made my ears perk up a bit. I have had the same sort of situation and brought it to the dealer, but was never able to replicate it for them.

It does occur intermittently, but I also found that grabbing is conjoined with the "putt-putt" sound that the brakes make when slowly taking one's foot off the brake (the pressure relief system in the right front of the car) when at a complete stop.

It's a strange quirk, but I treat it as just another part of my car's personality. Even my girlfriend has a few quirks, but I still love her too.

~Andrew

 

it has been relatively dry here so i have never heard or flet anything resembling squeal rattle or vibration.

i just rotated my tires last week and i noticed that both front and rear wheels spin freely without the hint of drag on them and the discs on the front show slight signs of rust on the rotor which tells me that i must be doing something right as it seems that they are not being used very often.