Juddering Brakes

[caherass]

Hi All,

My car is juddering under braking. No problem when not braking, so not wheel balance. I fitted new discs and pads only last year, but Zimmermann discs, so not OE items.

Could it be anything else other than discs and pads?

James.
1994 993 C2.

 

[sailor]

James
My brakes juddered like hell recently but it was to do with lack of use, a buildup of rust on the discs, plus worn pads.Cured by disc skimming and new pads.
Could it be early actuation of the ABS due to a sensor fault?
JohnC
993TT430

 

[lauris]

sounds like brakes,

if car has been wet or washed, and then left for a few days,,, common, when people wash the car before putting in garage !

rust can build up between pad and disk,,, and this can cause light to medium judder when braking,, generally cleans off during driving within 20-30 miles,,, town use etc,,,

look at your disks and see if there is an abvious spot where the they have corroded,, if they are all completely shiny, then disks may be warped,,, but this generally only happens when you track the car and get huge amounts of heat into them,,,,

cheers
scott....

 

[Stewart Rix]

I've heard a couple of sources recommend a periodic hard brake from higher speed(making sure its clear behind you obviously!) if the car tends to be used to trundle around town - apparently the inside pads don't tend to get as much wear under light braking, although personally I can't quite follow that logic, assuming the caliper is correctly set and the pistons are working properly. I had warped OE discs (not from trackday I might add and replaced under warranty) and they certainly caused quite a violent shake on light to medium braking.

 

[Richard Dawson]

Do you use your car often?

If not then pad marks can easily develop which cause nasty judders. It is also worth checking if the pads are moving freely in the caliper.

I have also heard that the cross drillings can also fill up with brake dust causing problems. The joys of cross drilled discs.

It is a shame there is no alternative that is not cross drilled.

 

[jmspear]

warping v rare, lot of disk thickness and think about how much it would need to warp! more likely deposition of pad material on disk face which builds up and causes judder, try a clean with wet and dry before you go down big expense on new parts or mid expense on skimming. It has worked for me and also for a friend on his C4S both with track day induced judder

John