Pontiac Sunfire 1999 shaking when applying brakes

S

sly30

New member
Joined
Oct 30, 2011
Messages
5
Reaction score
0
Points
0
Hi,

My oncle just bought a 1999 pontiac sunfire and it as a problem that we can't figure out. When you press the brakes on pavement more then on a dirt road it shakes alot on the driver side. So this is what we tried so far:

-first thing we changed was the rotor
-grease up the caliper to make sure it moves back and forth
-changed the hub with the bearing
-changed the drive axle
-changed abs sensors
-disabled abs to see
-changed the strut
-changed both control arm bushings on that side.

Please any help would be appreciated, we're out of ideas.

Thanks
 
If you haven't...try rotating the tires.
Other possible causes...worn ball joint,or tie rod. Broken belts,or out of round tire.(rare, but can happen) Incorrect torque applied to the lug nuts,or bent wheel.

Incorrect wheel alignment.

You mentioned the changing of the rotor. Was just one rotor replaced,and were the pads replaced at the same time?
 
Thanks for replying, i forgot to mention we did rotate the tires and the problem is still there. The tie rod and the ball joint seemed ok nothing loose. At 60 mph it doesnt shake at all so i dont think it could be wheel alignment but when releasing the gas pedal at about 60 mph you do hear a little knocking, you can barely hear it. It only shake when you press the brakes, lets say we're going 30 mph and press the brakes lightly you'll feel it shaking and knocking on the driver side only. oh yeah and we did only changed the rotor on that side since the noise comes from the driver side and when we changed the rotor we didnt change the brake pads the were ok, since the rotor wasnt the problem we figure we should keep the same pads. As for the torque of the lug nuts we used a impact its not a torque wrench but it does tight pretty even.

thanks again for the help
 
The wheels really should be torqued. Most impact tools have over 300ft.lbs of torque. Most lug nuts require less than a 100lbs of torque.

Just me,but I'd replace the brake pads. I had a similar problem with a 96 Olds 88. Both front rotors and the pads had less than 20k miles of use on them,and appeared as if they were in excellent condition. After replacing the parts the problem went away. The thing that makes me think you may have another issue is the clunking,or whatever noise you have going on. Clunking equals loose parts.

One thing I noticed on these cars is the motor mounts are prone to ware. I had one making an engine to frame contact sound. After replacing the motor mount on the passenger side the noise was gone. As well,there was an awful wobble in the right front wheel at about 35-45mph. Replacing the mount did help in reducing the wobble as well. I believe the car still needs a lower engine control strut,and of course a good alignment.

Sorry,but I have no idea if there is away of measuring the ride height of the engine in order to tell if the mount is sagging. The mounts don't break as far as I can tell,they just sag,which changes the angle of the engine in relation to the axles which can put the axles in kind of a bind.

Also,the mount on the drivers side is not the best I've ever seen. Its really kinda chicken crap. This is another thing to check since you have a clunking on that side of the car.
______________________________
 
Ok thanx for all the suggestions, i really appreciate it. I'll let you know when we find the problem.

thanx again
 
thanx for all the suggestions, i really appreciated it and i'll let you know when we find the problem.

thanx again
 
you could give this a shot, something similar happened on my Ranger, but drum brakes. Change the brake fluid. Dunno how, dunno what, but it worked.
 
When you get the shaking effect, is the steering wheel shaking or the body of the car? A brake drum in the back that is out of round will cause the body of the vehicle to shake.
______________________________
 
You must log in or register to reply here.

Share this page

Back
Top