brake judder still after new rotors and pads

[chapel gate]

changed these a couple of years ago actually after one of the original rotors sheared in two! had always had a judder on braking and after replacing with oem rotors and pads I thought the judder would be a thing of the past.... it wasn't. so I threw my tools down and forgot about the problem for a couple of years.

now I want to revisit and sort it out cos im bored of it now.

any thoughts chaps?

 

[Chris]

Judder all the time?

 

[chapel gate]

only when braking, some times worse than others. not horrendous, but not right.










100!

 

[Chris]

Yes I realise only when braking. But all the time when braking, or braking heavy or at speed, low speed....

 

[chapel gate]

probable not all the time. more so at speed I would say, and maybe more so on heavy breaking.

 

[Chris]

Taking on board that you will have looked at all the obvious stuff, so we won't say stupid stuff, I would suggest putting a dial indicator on each disc with wheel nuts on and check run out. The rotors may not be warped but is there anything stuck behind, or are they pulled onto the hubs fully? Easy check, will tell you a lot. Outside of that and wheel bearings, I am not sure what it would be. Last thought would be jammed diagonally opposing pistons in the front calipers. As you brake, the opposite pistons actually distort the disc a little causing vibration. This doesn't happen with directly opposing pistons

 

[silvercruiser]

Im not sure how or if possible on an 80, but when i had an RS turbo Many moons ago, it kept warping discs, after going through the calipers replacing etc and repalcing discs with origninal fords stuff. it was the hubs that had warped so changed these and another new pair of original ford discs and it was all good.

 

[chapel gate]

cheers chris, will try the dial indicator. no play In wheel bearings. pretty sure hubs are seated correctly.pistons moved freely on last pad change.

hate niggles like this, no obvious cause, not bad enough to spend hundreds of pounds changing out parts, but bad enough to be annoying...

got a few of these at the moment.

 

[Dave2000]

IIRC the discs are bolted to the rear of the hub so how will having the wheel nuts on help Chris? The setup is different on the Ford for example as the disc is on the front face.

regards

Dave

 

[Chris]

Err, the back ones aren't Dave......

 

[Dave2000]

Hands up and apologies. I was taking the shudder to be through the steering wheel so thinking front brakes.

Hmmmm question for admin, just where is the 'foot in mouth' emoticon?

regards

Dave

 

[clivehorridge]

Probably totally off the mark, but years ago I had a similar problem on an old ford 1600 GT and after new pads and rotors, I was equally disappointed to still have noticeable judder.

Eventually, I found play between the pads and the caliper. Imagine with some brake pressure applied, the rotor complete with pads, would move forward and backwards about 2mm. The calipers had worn where they retain the pad rotationally. (Goodness knows if that makes any sense to anyone).

I made up some shims to fill the gap and it cured it. I was so pleased to resolve the issue, I went out and bought new calipers. They cost about a months wages IIRC.

Did over 250 k miles in that car, changed the engine twice, but had it for ages

 

[Chris]

Well one thing's for sure, it's bound to be something.

Have you had your leg checked? It might be a problem with your knee ....

 

[frank rabbets]

You can get brake judder with discs being of ununiform quality metal through their body. The disc can measure OK but might have soft spots in it. This can cause judder similar to ABS judder.

 

[Chris]

Well that's what you get from fitting genuine Toyota Parts Frank.

 

[chapel gate]

ok, payed more attention going to work today. its from the front. judder might be too harsh a description. it does do it coming to a stop its just more subtle. imagine a large, slightly warped fly wheel slowly coming to a stop, that's how it feels at the peddle. the "flywheel" is rubbing slightly so it stops sharply as it runs out of energy.


it does make sense cheers clive. something to have look at.

 

[Chris]

Wish you'd said
That's an ABS sensor

 

[chapel gate]

my ABS sensors are on the floor in the corner of the workshop next to the ABS pump...

 

[Chris]

That's queer...That's the classic sensor failure. Hmm, maybe it's an ghost problem like people who still have pains in limbs after amputation!!

OK well on with the tests

 

[joinerman]

Yes i know that feeling all to well Chris