disc brakes grabbing at speed

[WmWatt]

During a test drive when the car got up to 80 kph (50 mph) the new front disc brakes came on by themselves. I eased off on the accelrator and tried again, 5 times in total. Three times the brakes engaged, two times not. There is about 50-60 miles on the new brakes (calipers, pads, rotors). Is there a standard fix for this problem? Thanks.

If it's not something I can fix it I'll take it back to the dealerhsip on Monday. The mecahnic there took the pads off and put them back on modifying the retainer (return) springs I had on backwards. I guess he didn't test drive at speed. As metnioned in another thread, thanks to the mechanic the wheels are no longer heating up.

[GenevaDirt]

what do you mean by came on......

[zoom zoom]

I'd be willing to bet, if he was ASE certified, he probably said the brakes retaining clip was on backwards, wether they were or not, and now he managed to not install them properly.

When I changed my front brakes the first time, I didn't have a haynes manual, andi forgot to put the passenger side clip back on.

I found it laying in the driveway later..thought it was cool, and threw it away before I realised what it really was.

20+k miles later im still stopping with the same brakes, and its not causing any noticable drag, but I'm sure its not recommended.

[Damkid]

The mecahnic there took the pads off and put them back on modifying the retainer (return) springs I had on backwards.

Return Spring?? umm i think what your thinking about is almost like a wire that goes through some pins? that "wire" simple stops those pins from sliding out and those pins hold your brake pads from falling out of the calipers, there is no return spring on the calipers

I'm having a hard time understanding how brakes can come on by themselves when they want to, the only time i've seen brakes stick on is by a seizing caliper or a callapsed (sp?) flex lines

[FB71]

During a test drive when the car got up to 80 kph (50 mph) the new front disc brakes came on by themselves. I eased off on the accelrator and tried again, 5 times in total. Three times the brakes engaged, two times not. There is about 50-60 miles on the new brakes (calipers, pads, rotors). Is there a standard fix for this problem? Thanks.

If it's not something I can fix it I'll take it back to the dealerhsip on Monday. The mecahnic there took the pads off and put them back on modifying the retainer (return) springs I had on backwards. I guess he didn't test drive at speed. As metnioned in another thread, thanks to the mechanic the wheels are no longer heating up.

did you change the master cylinder during this swap? Sounds like the cylinder is not returning to full released position. You may need to shorten the adjustable pushrod in the booster.

[WmWatt]

Clarification: As the car was accelerating it started to slow down as if I had stepped on the brake. Went out this afternoon to try again but the car would not do it. I was able to reproduce the effect by applying the brake with left foot while right foot was on gas pedal. I drove around tapping on the brake pedal a few times to see if the pads just needed to self adjust or something. I don't know exactly what the mechanic did. I just have what is typed on the work order (complaint, diagnosis, work done). Says he reinstalled pads. Logic points to last thing done to brakes as the cause of new behaviour. Whatever he did stopped the wheels from heating up. Problem seems to have gone away. Thanks for the comments.