Thought's please on juddering whilst braking
Discussion
As you had new disc, it can't be this: https://www.reddit.com/r/WTF/comments/zv47p/cute_g...
But it was a year ago!
John
But it was a year ago!
John
in my personal experience, juddering that only occurs at higher speeds upon braking and its frequency is mostly independent of actual wheel speed, is caused by worn suspension mounts such as rubber bushes or ball joints. At lower speeds and light braking, you won't feel anything. it only happens once a certain speed and braking force is exceeded. the forces generated by the braking unload some of the suspension bushes and joints leading to free play in the suspension. This tens to let them oscillate.
ARBs don't do anything unless you are in a turn, so they won't cause this.
have all suspension bushes and ball joints inspected on your front end, replace the worn components and the judder will be gone.
In order to inspect, you need to unload the suspension of that corner, sometimes you even have to disconnect one end of the shock absorber. Otherwise the suspension is loaded and you won't feel any free play when you wiggle the wheel or wheel hub. That is why so few garages are able to properly diagnose such issues. They rather sell you new pads and brake disks for lots of money, only to find that it makes no difference. They then sell you new hubs or machine the rotors on the hips as they suspect hub run-out. Again after parting with lots of cash you'll find it does not cure the issue.
A simple 30 quid ball joint or rubber bush later all issues are gone.
An other tell-tell sign that sometime, not always, points in this direction is a ever so minute free play or dead zone in the steering wheel at speed in the center position or upon changing turn direction of the steering wheel. This happens because the pinion or ball in the worn joint switches from one "resting position" onto the other side of the joint as it has free play. if all joints are tight, you don't have any of this perceived free play in the steering.
These joints failing is very common across all brands of cars. BMW, Audi, Mercedes, Ford, Lotus, Toyota, VW, .... (these are the ones I have either fount it myself or within the family) They fail in as little as 20000 miles. BMW e36, e46 and e87 being the worst.
Remember to check steering geometry afterwards.
ARBs don't do anything unless you are in a turn, so they won't cause this.
have all suspension bushes and ball joints inspected on your front end, replace the worn components and the judder will be gone.
In order to inspect, you need to unload the suspension of that corner, sometimes you even have to disconnect one end of the shock absorber. Otherwise the suspension is loaded and you won't feel any free play when you wiggle the wheel or wheel hub. That is why so few garages are able to properly diagnose such issues. They rather sell you new pads and brake disks for lots of money, only to find that it makes no difference. They then sell you new hubs or machine the rotors on the hips as they suspect hub run-out. Again after parting with lots of cash you'll find it does not cure the issue.
A simple 30 quid ball joint or rubber bush later all issues are gone.
An other tell-tell sign that sometime, not always, points in this direction is a ever so minute free play or dead zone in the steering wheel at speed in the center position or upon changing turn direction of the steering wheel. This happens because the pinion or ball in the worn joint switches from one "resting position" onto the other side of the joint as it has free play. if all joints are tight, you don't have any of this perceived free play in the steering.
These joints failing is very common across all brands of cars. BMW, Audi, Mercedes, Ford, Lotus, Toyota, VW, .... (these are the ones I have either fount it myself or within the family) They fail in as little as 20000 miles. BMW e36, e46 and e87 being the worst.
Remember to check steering geometry afterwards.
Edited by Ive on Saturday 23 January 10:47
I too have an ST220 and have experienced the exact problems the OP describes.
I brought the car on October 2015 and previous owner had changed front discs and pads about 6-8 before. My mechanic initially said warped discs, but having done around 6k since October, the juddering has just recently (i.e. last two weeks) stopped of its own accord.
I had the MOT early this week and it passed with no advisories. The car otherwise drives and tracks perfectly.
I am not sure why its got better, as I did not change anything on the car at all, except for rear wheel bearings 4-5 weeks ago.
I brought the car on October 2015 and previous owner had changed front discs and pads about 6-8 before. My mechanic initially said warped discs, but having done around 6k since October, the juddering has just recently (i.e. last two weeks) stopped of its own accord.
I had the MOT early this week and it passed with no advisories. The car otherwise drives and tracks perfectly.
I am not sure why its got better, as I did not change anything on the car at all, except for rear wheel bearings 4-5 weeks ago.
Yes, rear wheel bearing come as a complete hub. I fitted SKF wheel bearings which are OE quality. Vibration did not disappear with the new rear wheel bearings.
My line of thinking (based on limited technical knowledge) is that as the discs and pads have worn, they have perhaps 'settled' and any deviations from normal have corrected themselves.
It's good to know you got it sorted BaldPuma - I will wear down current discs and pads and replace with Mintex in the future.
My line of thinking (based on limited technical knowledge) is that as the discs and pads have worn, they have perhaps 'settled' and any deviations from normal have corrected themselves.
It's good to know you got it sorted BaldPuma - I will wear down current discs and pads and replace with Mintex in the future.
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