Investigated brake judder, opinions sought please!

[wafter]

As a few may remember a couple of years ago I bought a Civic that suffered judder / steering wheel oscillation under braking.

The disks were shafted and I assumed they'd been cooked and warped as they were right down to the wear limit. I replaced them and all was well for a few thousand miles, then the judder gradually came back. Long story short it's now on its 3rd set of disks having behaved exactly the same with each set.

Yesterday I finally pulled my finger out, had the wheels off and measured the thickness (taken with a micrometer at 8 equally-spaced points around the disk at around 10mm inboard from its outside edge) and runout (measured with a dial test indicator at approximately the same points around the disks, around 5mm inboard from the outside edge).

Driver's side:
Total thickness variation: 0.020mm
Total runout: 0.043mm

Observations: pads drag on disk somewhat while rotating, variation in friction with position of disk that doesn't nec. correspond with areas of high / low thickness or greatest area of runout.

Passenger side:
Total thickness variation: 0.078mm
Total runout: 0.130mm

Observations: disk noticeably easier and more consistant to rotate than D/side, with no perceivable variation in force required to turn.


So, on the one hand it appears that the d/side caliper might be dragging a little; although economy is decent, there's no smell and the wheel doesn't get hot so I guess this is minimal.

The p/side disk is clearly a lot less consistant, both in terms of thickness variation and most notably a significant amount of runout; making me think that this is the side that's causing the problem. Since I've been through numerous sets of disks the problem is clearly the result of something else on the car - I'm thinking the most likley culprit is a warped hub flange..

I want to get this sorted but have limited facilities so realistically any work will have to be done by a garage. The car's worth sod all and being run on a shoestring so I don't want to sink hundreds into fault-finding, but am open to the idea of paying to have a specific job done if I can be reasonably confident that it will resolve the issue..

As such I welcome the input of anyone who has anything constructive to offer based on the available evidence - thanks

 

[biggs682]

Are you using genuine parts ?
Have you tried swapping the disc's side to side ?
Does the Civic pull when you are breaking ?

 

[wafter]

Are you using genuine parts ?
Have you tried swapping the disc's side to side ?
Does the Civic pull when you are breaking ?

Parts are aftermarket but decent brands and Honda stuff's pricey.

I've not tried swapping the disks (difficult given my facilities) but I don't think it's an issue with these since I'm on my third set and they all start out performing fine - it's like an issue elsewhere causes them to wear in a pattern that promotes judder and self-perpetuates; as I might expect from a warped hub flange .

Braking's fine other than the violent oscillation (which is speed dependent; worse between maybe 40 and 30mph) - no pulling to either side.

Thanks

 

[CXRAndy]

Start with the basics. Check the hub for run out with a dial gauge. The hubs have to be near perfect with no high spots on the mating surfaces .

New discs and full service of brakes, slide pins and new hardware mounting for new pads.

Check run out on new discs so you have reference as they age

 

[wafter]

Start with the basics. Check the hub for run out with a dial gauge. The hubs have to be near perfect with no high spots on the mating surfaces .

New discs and full service of brakes, slide pins and new hardware mounting for new pads.

Check run out on new discs so you have reference as they age

Thanks - unfortunately I'm unable to measure runout of the hubs as I can't get the caliper carriers off without the car in the air. I did ask the mechanics to check the runout on the hub when they replaced the disks last time, and I was given a value of 0.1mm (no more info as to which one) which is apparently the upper end of what's considered acceptable.

I wish I'd checked the runout when the disks were new, however don't own a DTI and had to blag one to do this job.

All this is galling considering what I could have achieved if I still had access to a fully fitted workshop

 

[sleuthey]

likley culprit is a warped hub flange..

Like when you try and find a undertensioned spoke, can you not put the wheel back on, spin it and gradually move a marker pen closer till it touches? Then rotate by 90 degrees and measure the gap between the tip and wheel. Not the most accurate but might give you an idea.

 

[wonderloaf]

We had an 05 Civic which had the symptoms you describe and it came down to a stuck caliper piston, the local garage refurbed the caliper and all was fine.
Haven't read the thread fully so apologies if you've already ruled this out, thought I'd mention it anyway.

 

[biggs682]

Parts are aftermarket but decent brands and Honda stuff's pricey.

I've not tried swapping the disks (difficult given my facilities) but I don't think it's an issue with these since I'm on my third set and they all start out performing fine - it's like an issue elsewhere causes them to wear in a pattern that promotes judder and self-perpetuates; as I might expect from a warped hub flange .

Braking's fine other than the violent oscillation (which is speed dependent; worse between maybe 40 and 30mph) - no pulling to either side.

Thanks

Being an ex Honda parts manager I am aware of the price but just wondered.

If it was the hub run out surely the fault would be straight away?

I presume new pads were fitted each time ? And mating surfaces cleaned ?

A sticky caliper is likely do you have a local not station who could put it on the brake rollers to see if it shows that a caliper is sticking

 

[Jody]

Don't assume expensive/high end brands are any good. I had really bad judder almost from new with one manufacturer.

It took me a while to work out and was only resolved by switching to anther manufacturer (Pagid). It's been right ever since

 

[T4tomo]

I recommend using a up hanger from the fork bridge, the shorter cable run to the caliper usually eliminates judder

 

[PK99]

I presume new pads were fitted each time ?

My antennae twitched at that comment. Years ago, our Civic developed a brake judder which a Mechanic mate recognized as the (then) Brake Pad wear indication built into the Honda pads.

 

[wafter]

Thanks all!

Like when you try and find a undertensioned spoke, can you not put the wheel back on, spin it and gradually move a marker pen closer till it touches? Then rotate by 90 degrees and measure the gap between the tip and wheel. Not the most accurate but might give you an idea.

That's an appropriate analogy for the deformation. A better indication is to use a dial test indicator; however as above while I used this method with success on the disk, I can't do so on the hub as this requires removal of the disk which is outside my abilities with my currenty facilities

We had an 05 Civic which had the symptoms you describe and it came down to a stuck caliper piston, the local garage refurbed the caliper and all was fine.
Haven't read the thread fully so apologies if you've already ruled this out, thought I'd mention it anyway.

Thanks - this is really reassuring; both because a caliper is an easier thing for me to investigate and is also potentially corroborated by my findings. This would potentially fit with the problem disappearing when new disks are fitted as this requires the pistons to be wound in on the calipers (thus freeing up/ over-riding the binding), then the problem slowly returning as the piston begins to bind in the caliper again.

A binding caliper would also be in-keeping with the fact that one side feels tight, and that the oscillation / vibration seems worst with light to moderate braking. If I really, really stand on the brakes (which I rarely do under normal conditions) the problem appears to lessen / disappear; which again seems logical.. although I'd previously put this down to deformation / slip in the tyres under high loads.

Finally it should be within my ability (providing I can free the caliper off enough) to remove it, wind the piston back in, and test to see if the problem has got any better.

Being an ex Honda parts manager I am aware of the price but just wondered.

If it was the hub run out surely the fault would be straight away?

I presume new pads were fitted each time ? And mating surfaces cleaned ?

A sticky caliper is likely do you have a local not station who could put it on the brake rollers to see if it shows that a caliper is sticking

Cheers - I thought maybe a hub runout issue might give increasingly worse symptoms if the deformation caused the disk to wear unevenly during use.

Yes, new parts throughout were fitted each time and the mating faces given a good scrub with a wire brush.

As above I think a sticky caliper is well worth investigating as it seems like a likely culprit as well as being a potentially straightforward thing for me to investigate myself.

Surprisingly (at least to me) the car made it through an MOT in this state and I get no obvious issue with differential braking load across the front of the car, so I can only assume it's OK in this regard. Fuel economy remains OK (weather and traffic permitting) and the potentially affected wheel is no warmer to the touch than the other side after a 20 mile drive to / from work.

I recommend using a up hanger from the fork bridge, the shorter cable run to the caliper usually eliminates judder

Thanks - can you advise where I'd find the fork bridge on a 2003 Honda Civic?

 

[Fastpedaller]

A friend had a similar problem with a Ford Escort many years ago - he got discs skimmed, new ones etc. It was only when he took it for MOT that the tester noticed it had Sierra alloy wheels on it, but the wheel nuts were for steel wheels. The nuts (and wheels) seemed tight to my friend, but were 'bottoming out' on the hubs, therefore under extreme load the wheels were able to move slightly. Correct wheel nuts sorted it. Have the wheels been changed from the maker's spec?

 

[wafter]

A friend had a similar problem with a Ford Escort many years ago - he got discs skimmed, new ones etc. It was only when he took it for MOT that the tester noticed it had Sierra alloy wheels on it, but the wheel nuts were for steel wheels. The nuts (and wheels) seemed tight to my friend, but were 'bottoming out' on the hubs, therefore under extreme load the wheels were able to move slightly. Correct wheel nuts sorted it. Have the wheels been changed from the maker's spec?

Thanks - wheels and nuts are all original though as far as I'm aware. At some point I'll try to remove the caliper, soak the piston in penetrating oil and attempt to wind it in. If this cures the issue I'll pay a grown up to replace it; otherwise I'll keep on looking!

 

[Fastpedaller]

Beware that th penetrating oil may have some solvents which are incompatible with the caliper piston seals!