I have a 94' volvo 850glt.I just replace the from brake rotor and pads and everithing is fine, the brake system works great. The problem is that sometimes (not always) the entire body start shaking hard (only a low speed, in high speed nothing happen), It only happen when I press the brakes (decreasing the speed around 10miles per hour until the car stop). the problem happen just a few second, not always do that,and is gone after I release the brakes, after that the car keeps funcionating just fine and the brake system works normal not dragging sounds or pulling to one side occurs. I am thinking about the transmision or suspension because it sound like my car's tires are scraping the chasis or something. I checked the space betwent the tires and chasis but everething seens normal.

Plese answer me what do you think it can be?
Sincerely,
Jorge

Jorge,
I wonder if your brake pads may be too hard. You will wind up "warping" the rotors and scraping up the rotors. My car's previous owner got tired of replacing pads and cleaning brake dust all of the time so he put on harder pads. Great, no dust! Warped rotors had to be replaced after 5,000 miles because the wore too thin to be machined. The pads still looked like new!

Klaus
--
98 V70Rawd(101Kmi), 95 854T(85K mi), 75 164E(173K mi)

Thanks Klaus for your comment.

Sounds like you put aftermarket rotors and pads on.

Yes, I did, and I've been drive my car for more than 3 weeks with my new front rotors and nothing has been happened, the vibration seems to came from all the wheels and I think it can be the ABS controller.

thanks friend for answer my question. where are you?

I put aftermarket pads on before and they tend to shift around abit. I compared the brackets on the pads to OEM and they were abit smaller (on the ones I bought) Higher speeding braking was fine but when i slowed down it would shake the car. (sometimes it was fine and other times it would shake or grind) I found that almost every aftermarket part i've put on gives me problems. I'm sticking to oem from now on.

You mentioned abs. I really doubt that because abs only kicks in when the wheels lock. If theres any type of failure in the system it will simply shut down and turn on the abs light.

I'm in Toronto

Sound like you might have an issue with the rear brakes or perhaps a sticky caliper.

That's what I thought but the vibration does not come from the rear brake but seem like this came from all the wheels. I asked the same question at www.texasvolvoclub.com and a friend told me that it can the the ABS controller.

Anyways thanks friend for answer my question.

I have a 2000 S40 that was vibrating really bad. I found it was the motor mount. After this was repaired the car drove smoothly.