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Yes, I think so. Not cross drilled though.
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Yes I think so.
I thought as much being a 1.8. If not I was going to suggest getting a pair of calipers and vented disks off a scrapper to see if the increased contact area made things any better.
Do the wheels turn freely when jacked up? Do they free up straight away when foot taken off the brake? Do some high level brake testing - car on axle stands with wheels attached!
If you've ruled out driving style then next thing I'd do is replace the calipers. For £100 you'd re-coupe your costs in no time at the rate you go through disks! At that age and mileage the seals will have done good service.
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Not necessarily bad advice mfarrow, the problem is where to stop spending?
I would suggest that brake hoses could well be the problem; just holding the brakes on a little too long even?
Could be other problems too. Probably worth a visit to a decent mot station (1 with an experienced mechanic) to do a roller brake test and see if/ what figures he can produce and if he can analyse any problems (which wont be enough to fail an mot).
Might be able to find a wheel or 2 just holding on longer, or working slower etc etc.
There again, it may just be cheaper to keep replacing discs, as long as the time interval doesnt get any worse?
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They feel free enough when I spin the wheels with the bakes off.
I note the MOT report showed quite a high "variation" reading on the print out, but overall efficiency was more than sufficient to pass.
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when you replace the disc's do you do any specific bedding in of the disc's/pads ?
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Hi,
When you change the brake discs, have you ever had a run out test conducted on the wheel hubs?
It's not uncommon for these to be the problem, which is why you don't get long from each set of discs.
You would need DTI gauge set up properly to measure the run out of each hub.. If one was buckled/warped it will show up on the gauge.
James
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I don't have such a guage, but perhaps my local garage could do it for about £30.
It would seem strange for a hub to warp. If so, perhaps it's been like that since new!
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Whilst it would be interesting to put such a gauge on and measure, and let us know.....
In reality, if the hub was "out" it would affect a new disc as much as an old disc. In which case I would suggest it is not worth the expense of finding the answer.
No pont in spending good money for a pointless result unless you could get access to such result free or with money you are prepared to lose.
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Yorkiebar, you do have a point. The brakes are fine with new disks, so presumably the hub is OK.
Since nobody has, so far, suggested that I should use something like Rossini or Brembo instead of the stock items, I presume the general consensus is that they're not worth the extra money - not on a car worth £700 anyway.
Thanks everyone for your help. One thing I will try is to get into the habbit of using the hand brake when stationary if the disks are likely to be hot.
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I dont think there is anything to be gained by such "named" discs.
Would stick to Delphi, Mintex or similar or even QH discs or similar quality aftermarket discs, and try the change in braking style.
I think more would be achieved with analysis of the brakes on a brake tester than would be achieved by different brands or measurement of run out etc.
A decent mechanic on a brake tester will be able to see how even the pressure is when brakes fully applied, how it releases, how equal (or not) as its apllied etc etc and give you more info that way.
If you want to spend any money to try and identify any problem; thats the route I would choose.
(As a footnote, I have been criticised before for suggesting that a brake tester can do anything other than just report pass or fail at mot time !)
Edited by yorkiebar on 29/10/2008 at 11:45
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A slightly buckled/warped hub is a very common cause of brake vibrations through the car.. And new discs will cure it... for a while.. If you think about it, if your going through brake discs, both OE and aftemarket ones, every 15000mls, does that not tell you that there is an underlying cause as to why the brake vibration/shudder re-occur's.
I will also guarantee, that when you open up a brand new set of brake discs, on the paperwork/instructions that is inside the box, there will be some form of notice advising you to have the hubs checked for runout PRIOR to fitting, as no warranty will be honoured if this has not been checked... Or something along those lines.
I used to work for a Ford main dealer about 10 yrs ago, and it was fairly common to have to change front hubs as well as the discs to eliminate brake shudder.We would do a run out on the discs first, and then strip off the discs and do a run out on the hubs. The results of both tests determined if hubs would be required as well as discs.
Get the run out checked on both front hubs. If they are ok, then at least you can rule it out, but i think you will find at least one hub has excessive run out.
hth
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I think more would be achieved with analysis of the brakes on a brake tester than would be achieved by different brands or measurement of run out etc.
A run out test will eliminate or confirm any abnormalities on the front hubs.
A decent mechanic on a brake tester will be able to see how even the pressure is when brakes fully applied how it releases how equal (or not) as its apllied etc etc and give you more info that way. >>
If there was a pressure difference either at applying the brakes or releasing them, the most likely fault would be a brake pull to whichever side had the most pressure.
No way would this scenario cause a brake vibration... imo.
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I have also noticed a slight vibration while driving at about 70 - 75, feels almost like a wheel out of balance.
Have had the wheel balance rechecked, and it looks OK, so perhaps this could be another symptom of a warped hub.
I wonder how they become warped in the first place? Overtightening of wheel nuts?
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?A slightly buckled/warped hub is a very common cause of brake vibrations through the car.. And new discs will cure it... for a while.?
Dont understand how! If the hub is out; its out, with new disc or old disc!
?If there was a pressure difference either at applying the brakes or releasing them, the most likely fault would be a brake pull to whichever side had the most pressure.
No way would this scenario cause a brake vibration... imo.?
The pressure difference may be holding the brakes on too long, etc, causing excess heat. This coupled with keeping the footbrake on when stopped after using brakes will magnify the problems mentioned earlier.
What we are looking for is a fault that is causing the problems(s) without spending a fortune.
A sticking calliper for example will exaggerate any unevenness. A brake hose not releasing will be holding brakes on longer. Neither will necessarily cause any uneven pulling.
In an ideal world run out is measured whenever discs are replaced. In the actual world I wonder how many times run out is measured. If new discs are fitted and the vibration goes; then the end result is correct!
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?A slightly buckled/warped hub is a very common cause of brake vibrations through the car.. And new discs will cure it... for a while.?
Dont understand how! If the hub is out; its out with new disc or old
disc!
Fair point!! Just using my personal experience to try and help someone solve a problem.. and my personal experience of this particular problem, after many sets of brake discs fitted but problem still exists, is a slightly buckled/warped hub.
What we are looking for is a fault that is causing the problems(s) without spending a fortune.
I totally 100% agree with this.... But the op has already stated that he could get the run out checked at his local garage for around £30.. Money well spent if it diagnose's a hub fault... money down the drain if the hubs are ok... but worth the risk is it not.. £30 is not going to break the bank, but will at least either confirm or not wether a hub is the root cause of the problem.
A sticking calliper for example will exaggerate any unevenness. A brake hose not releasing will be holding brakes on longer. Neither will necessarily cause any uneven pulling.
>
I doubt the op wants to start throwing brake calipers and/or brake flexi hoses at the problem... Although he could take it for a run and slow down without using the brakes and then get out and see if he can put his hand near any wheels to feel for any heat from a binding brake.
. If new discs are fitted and the vibration goes; then the end result is correct!
Not if the fault comes back after a few thousand miles it does'nt.
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It wont be the hubs if it is OK with new discs, albeit only for a while.
As I said braking hard from high speed and then leaving the brakes on after coming to a halt can warp the discs due to the difference in the rate of cooling between the majority of the disc and the area that is clamped by the pads.
Dont get ultra cheap discs and perhaps change your driving technique.
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To your knowledge, has the car ever had front wheel bearings done?
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To your knowledge has the car ever had front wheel bearings done?
No, I don't think so. I have owned it from 50K, and no mention of it in the history before then.
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sounds like you could be heavey on the brakes. I would replace the rears including the drums as I suspect they are glazed up at the rear making the fronts do the most work. I have copme across this on mondeo's before & once the rears are replaced including drums problem solved. Has it got pattern wheel trims on reducing the air flow through the front wheels preventing cooling. Use a soft pad as well, ferodo as this may help. Mintex are hard & can warp disc's with lots of braking.
I Doc
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The drums are probably original, but the shoes are quite new. You may be correct about the front doing most of the work - it failed its last MOT due to brake inbalance at the rear. New cylinders and refresh of brake fluid sorted that out.
The car has alloy wheels, so ventilation probably not a problem.
I'll maybe try ferodo pads and disks together next time I change them. I presume ferodo make disks too?
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I would recommend buying a set of second hand parts to switch to all discs with ABS. I did this because soon after buying a 2000 estate my other half had a serious near miss on a country lane.
I had never been happy with the brake feel of the car and having had Renaults, Peugeots and VWs with rear discs for last 25 years I decided it was well worth a go.
The result was very impressive as the front to back balance is very good. This in turn diminished the feel of overloaded front brakes working hard to stop the car. The setup was the best since my old Renault 12/17 days when I could actually setup the balance by adjusting the rear pressure regulator under the car.
My conclusion was that the Mondeo estate ABS setup was the optimum and the non ABS was just a cheap alternative to save Ford money when they did not reach the world wide sales figure. However I cannot be sure this would work so well on a saloon as the estate brake setup is that also used on the 4 x 4 whereas the saloons use different calipers and discs.
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