Quick Question...

[CraigT]

I read in another topic on here that to tell if your disks are warped you should run your fingers over the surface of the disk. If it has ripples its warped.

Anyway, since buying the car I can hear a rotational metallic sounding noise from the front disks when I have the windows down. Upon running my fingers over the surface of all four disks they all seem to have a rippled grove effect.

Is this normal or does this fit the description of a warped brake disk?

How does warping of the brake disks occur?

The car is currently under warranty and will get it looked at if this is the case

[zilli]

In most circumstances. If your disc is warped, you will feel it through the pedal... It will make the car judder or feel wobbly as you brake. Though I'm sure the ripples you feel are across the surface as opposed to running your fingers around the disc???

[cfc1]

Take the car to an MOT station and get them to put it on the break tester.. they will tell you what disc(s) is/are warped.. if any.

[martin_longbow]

Are the brake disks groved ? if the discs are groved then you will hear a click. The best way to tell if the discs are warped is to accelerate to a reasonable speed 50 or 60 mph then (on a clear road with no one near you) apply the brakes quite firmly. If the disc is warped you should feel a definate wobble through the car but more likely you should feel this through the pedal or steering wheel.

You mentioned the click was a metalic sound, possibly brakes needing a service and a clean up to check the overall condition of the discs, de-scale etc. Not a difficult job if you are into getting a bit dirty and have a few tools.

Discs should be changed anyway, they are a servicable part and typically do not cost too much to replace.

[DefiantFrog]

Now, warped discs... I've had 2 different theories on this...

1, the usual, disks got too hot, cooled in an odd way and went wobbly.

2, discs don't warp. Instead its down to our lazy driving and leaving the pads on the discs once you have come to a standstill (traffic lights etc). As the discs are hot, it causes a little bit of the pad to melt on to them thus causing an uneven surface around the disc. Then when you next brake the wobble appears a bit as the pad is going from disc to the slightly raised bit of the melted pad dust and back again.

Personally I have recently experienced option 2 here - with my hands moving a couple of inches from side to side as I brake because of the wobble (quite severe), and doing a few (10ish) high-speed hard brakes to near standstills in a row has removed the melted brake pad remnance from my discs, and I'm braking dead straight again.

Comments on this?

And Craig - get your brakes checked. I'll put my money on your pads are nearly worn through, and you are starting to get the metal of the pad (or metal strips in the pad itself as a warning they are running low) rubbing against the disc.

[martin_longbow]

Heard of this once before, but I think it was due to cheap pads, at least that's what we agreed was probable cause. Out of interest were you heavy braking when this happened?

[DefiantFrog]

Heard of this once before, but I think it was due to cheap pads, at least that's what we agreed was probable cause.

That would fit...

Out of interest were you heavy braking when this happened?

Maybe... ;)

[adam83]

First post so hello!

On to topic, I've been having a fair few problems with my rear breaks, a nasty grinding noise, and sometimes a huge knock - almost as if a stone/rock had flicked up of the floor and hit the inside of my arch. Glad I spotted this topic though, I was fairly certain that my disc brakes were warped - when I brake hard I have to fight the direction of the car, it just wants to swerve all over the place.

Anyone know of any decent suppliers in the midlands/staffordshire area for celica parts? would prefer some grooved/drilled discs but don't want to spend a fortune as funds are a bit tight at the minute.

Pic of my car :-)

[DefiantFrog]

Ooo, black and white, very arty! ;) Nice lookin motor, and welcome to the club!

You could try ToyAuto in Nottingham - http://www.toyautocentre.co.uk/. They specialise in Celicas and MR2s. Can't comment on service personally, but I've had them recommended to me before, and I think one of the guys who runs is (Ian, maybe?) loiters on here every now and again!

The grinding noise - is it there all the time? If its only there for the first few brakes, then its probably just corrosion wearing off you're discs from it being stood still for a while. If its there all the time then your pads have probably worn to the metal.

The knock - I don't know.

If you're swerving, thats probably not warped discs, that sounds like not all pads are applying the same pressure to your discs - could need your brake lines bleeding, could be some of the pads are too warn... Could be a few things. Get it checked out.

[adam83]

Ooo, black and white, very arty! ;) Nice lookin motor, and welcome to the club!

You could try ToyAuto in Nottingham - http://www.toyautocentre.co.uk/. They specialise in Celicas and MR2s. Can't comment on service personally, but I've had them recommended to me before, and I think one of the guys who runs is (Ian, maybe?) loiters on here every now and again!

The grinding noise - is it there all the time? If its only there for the first few brakes, then its probably just corrosion wearing off you're discs from it being stood still for a while. If its there all the time then your pads have probably worn to the metal.

The knock - I don't know.

If you're swerving, thats probably not warped discs, that sounds like not all pads are applying the same pressure to your discs - could need your brake lines bleeding, could be some of the pads are too warn... Could be a few things. Get it checked out.

Thanks for the reply, much appreciated.

I had the brakes of last weekend because I thought it may need some new pads, but not so... Still plenty of life left in them.

Grinding noise is there all the time - When I first had it, I braked very hard and about 20 mins after that I had a *clunk* noise come from underneath the car, a hell of alot of rattling, pulled over but couldn't see nothing, managed to get it home and I had this lose rattling noise every time i moved forward/backwards. Took wheel off, had a look, couldn't see nothing wrong so I put it all back together and problem solved....Now 2 months later its back.

When I had the wheel of last weekend and moved the disc it was grinding against the pads, so maybe need to have the calipers looked at? and perhaps get the lines bled...

This week has been a nightmare though, grinding has been awful and not had chance to get it in the garage as of yet. Just hope its nothing to serious, not had the car to long.

Thanks again for the reply. :-)

[martin_longbow]

Adam Hi

Have you checked the bearing, is there any free play on the wheel when jacked up, wheel on and tight?

Also get the rear disc's off and have a buchers at the handbrake setup, your noise could be coming from there. The shoes may be a problem or have become de-centralised.

For brake parts these chaps are helpful, supplied my groved and drilled all round

Clicky

[adam83]

Hi Martin_longbow

Cheers for the reply, and the link - will def have a look at the site some more and order some nice new discs.

Quick little update on the progress:

Stripped the rear wheel down today, and tried rotating the disc (completely jammed now). Basically, and I have no idea how this happened! but the drum brake (didn't even know GT's used a disc and drum on the rears - pretty damn clever) had completely been destroyed - pads had warn down to nothing and was grinding the actual metal of the shoe, a bolt had been completely sheered off, and a spring had been ripped in two. No idea how this has happened, and kinda shocked, worried at how much this potentially could cost me. Not a mechanic myself, but I don't mind getting my hands dirty and has def been good in having a look at my GT and knowing how it all works...well some of it.

So as it stands, the car works! I took the rear right drum off - well all the internalls anyway, so all I'm left with now is a brake cable. The discs all work fine and I've just got back from a nice little drive, the cars running great! obviously can't leave it in the state its in, cus i'm sure if i left it parked on a hill the car wouldn't really be all that stable with only one drum brake left to hold it.

Would like to say a big thanks for all your input though, I'm sure you saved me a packet from letting a mechanic trouble shoot the problem for me. :-)

Another quick questions, if anyone's willing to offer some advice. Considering getting my car lowered, it's on 17's at the minute all though that may change to 18/19's. Wondering what everone else has done when it comes to lowereing? just different coil overs....and how much have you had it lowered? any difficulties with speed bumps/rubbing on bends, etc....

Cheers all!

ad

[chris202]

Welcome to the club :)

Got lowering springs in me boot , been there for months - MUST get round to getting them on.

[adam83]

Welcome to the club :)

Got lowering springs in me boot , been there for months - MUST get round to getting them on.

Hi crismillencolin :)

Are you going to be doing the job yourself? had a look for some spring on eBay (of all places!), and considering doing it myself. How much are you likely to drop yours by? I was thinking about 40 mm all round, all thought the rear seems a little higher than the front. So maybe 30/40. :0S