97 740il shakes when brake @ low speed

[jfarley202]

I'm seeing a re-occuring problem, with the car shaking when I brake @ low speeds ( 40 and below). This comes almost 2 months after having the same problem diagnois as warped front roters which was turned.
What could be causing these rotors to warp so quickly ?

[xAUTOxRACERx]

When the rotors were resurfaced did you get new pads also? How are the rear rotors?

[Antiburn]

Check your front lower control arms and bushings. When they wear out on any BMW's the steering wheel tends to shake durring braking.

[jfarley202]

Yes the pads were repaced

[jfarley202]

Originally Posted by Antiburn

Check your front lower control arms and bushings. When they wear out on any BMW's the steering wheel tends to shake durring braking.

So if I understand this correctly, the control arm and bushing failure, is the underlining cause for the warped rotors ?

[Bear]

I have never had good luck having the European rotors turned as it seems they are almost at wear limit when they go bad. I would have the upper control arms and bushing (bushings primarilly) checked as they go bad quite often, and also I would replace the rotors.

[gibbz80]

Originally Posted by jfarley202

I'm seeing a re-occuring problem, with the car shaking when I brake @ low speeds ( 40 and below). This comes almost 2 months after having the same problem diagnois as warped front roters which was turned.
What could be causing these rotors to warp so quickly ?

I feel your pain! Just completed the replacement of my Upper Traction/Control arms last weekend after checking the entire front suspension, braking systems. This solved the problem. I have a 94 740il and found the parts at Vines Automotive for 105.00 including shipping.

stores.ebay.com/vines-automotive

Gibbz80

[mikebuk]

Hi Guys,
I have the same problem on my 97 750i. Your refering to upper and lower arm bushings is throughing me a bit as the front strut is held in place by two lower arms, one towards the front and the other to the rear of it (the arm with the 3" bush in it). Which is which? Cheers.

Mike.

[chevyguy93]

k. ive got the same problem, except its not just at low speeds. when your going fast and breaking, you dont notice it much until you get to a slower speed, maybe 60km/h and less. Ive already replaced the control arms and all that before due to other problems. anyways. should i go ahead and replace the rotors? i have a 93, so i got drum brakes in the back. maybe it has something to do with those?
it just feels as if someone is stepping on the brake, letting go, stepping on it, letting go, continuiously (while brake is applied). I have heard of a problem with cavaliers where they really tend to warp the rotors. Should i go ahead and replace them? It's been 2 years and its starting to get bad.

[mikebuk]

Originally Posted by chevyguy93

k. ive got the same problem, except its not just at low speeds. when your going fast and breaking, you dont notice it much until you get to a slower speed, maybe 60km/h and less. Ive already replaced the control arms and all that before due to other problems. anyways. should i go ahead and replace the rotors? i have a 93, so i got drum brakes in the back. maybe it has something to do with those?
it just feels as if someone is stepping on the brake, letting go, stepping on it, letting go, continuiously (while brake is applied). I have heard of a problem with cavaliers where they really tend to warp the rotors. Should i go ahead and replace them? It's been 2 years and its starting to get bad.

I can't see it being anything to do with the rear drums. If the drums are unevenlly worn you should be able to notice a 'pulsing' on the foot pedal as the high point on the drum passes the brake shoe. If the rotors are really out of shape, then the steering wheel will rock violently. You say "it just feels as if someone is stepping on the brake, letting go, stepping on it, letting go, continuiously (while brake is applied).", to be honest, this is exactly how the abs works! maybe there is a problem there.

Mike.

[chevyguy93]

ok. first of all, sorry people! i thought this was still teh cavalier section, i did a search for "rotors" lol, and found this post. so please forgive me for posting in the wrong place. hehe
ok. now. i think i should have been more clear. when i said it feels like someone is stepping on the brake, i dont literally feel it in the brake pedal. the car itself acts that way. so i dont feel anything in the pedal or steering wheel. Last time i had the front tires off i didnt notice a warp in the rotors, yet it could be very slight that i just did not notice it. and my abs dont work. light stays on, so i just unplugged the unit itself. hasnt caused any problems. So do you think i should replace the rotors? see if it solves the problem? or get new new cap things for the rear drums. (not sure what they're called!).
so thanks for your reply even though i posted in the wrong place. haha. if u can help me out more with that info above, it would be greatly appreciated. if not, i'll re-post in the cav section

[mikebuk]

Originally Posted by chevyguy93

ok. first of all, sorry people! i thought this was still teh cavalier section, i did a search for "rotors" lol, and found this post. so please forgive me for posting in the wrong place. hehe
ok. now. i think i should have been more clear. when i said it feels like someone is stepping on the brake, i dont literally feel it in the brake pedal. the car itself acts that way. so i dont feel anything in the pedal or steering wheel. Last time i had the front tires off i didnt notice a warp in the rotors, yet it could be very slight that i just did not notice it. and my abs dont work. light stays on, so i just unplugged the unit itself. hasnt caused any problems. So do you think i should replace the rotors? see if it solves the problem? or get new new cap things for the rear drums. (not sure what they're called!).
so thanks for your reply even though i posted in the wrong place. haha. if u can help me out more with that info above, it would be greatly appreciated. if not, i'll re-post in the cav section

No problem. Is it worse under heavy braking or light braking???

[chevyguy93]

well. if i do a panic stop, i dont really notice it. when i do light stoping, its very noticable. i can press the pedal down a little, and it i could feel it slowing down, then its as if i dont have the pedal pressed at all, then it slows down more, etc.

[mikebuk]

Originally Posted by chevyguy93

well. if i do a panic stop, i dont really notice it. when i do light stoping, its very noticable. i can press the pedal down a little, and it i could feel it slowing down, then its as if i dont have the pedal pressed at all, then it slows down more, etc.

When the pedal is pressed, are these braking-not braking-braking-not braking transitions fast i.e. fractions of a second or slow i.e. every second or more?

Mike.

[chevyguy93]

the faster im going, the faster u can feel the car pulsing when im braking. as i come slow down, the pulsing starts to slow down. its hard to explain. i'll just say it feels as if its a warped rotor. it has the same symptom.