Front Disk Strangely Warn

[goldgit]

Hi guys I have been a bit of a harvester of other contributors info, but have come across a strange problem on my 06 2.2 wt4x4, on both front disc the pads had worn a grove in both inside faces of the disc, the grove is 1.5mm deep and about 2/3 rds of the width of the pads and is dead central,the pads have similar wear with a step in the middle to match the grove in the disc, both sides are exactly the same with no wear to the outer pads or disc faces. the cenering works of the caliper are free and move easilly, cant understand it but dont want it happening again when i replce everything???????? any help would be much appreciated

[Mistermena]

How many miles on the clock? Not sure what the cause of this could be. But if you're after a new set of discs and pads have a look at the MTEC site as they are fantastic. Others night be along like Anch's who will peob be able to help you out with the whys.

[anchorman]

Given that the pads are original and have not been fitted with an unknown quantity, all you can do is change them and don't worry. Lower milage vehicles tend to suffer more with inner disc wear and ridges and it is caused really by corrosion and contaminants. Pads enjoy temperature to keep them healthy and clean but standing or low duty can cause said problem.

[goldgit]

Not original pads by the look of them, about 56k on the clock, what is of concern is the uniformity of the wear on both sides. going to remove the disc this morning (rain permitting) will take some pics and post them

[goldgit]

here are pics as promiced disc badly pitted, exactly the same both sides, MOT garage (reason for brake check) says one of the worst they have ever seen

[anchorman]

I've seen dozens with a similar wear pattern but I don't recall seeing that pitting - trust me when I say I've seen hundreds it could well be thousands.

I wonder if that was a poor casting.

[jedi134]

I too have seen that wear pattern on many cars inner discs, I just presume its normal? Maybe because more force is being asserted to the center of that pad as its the one that comes in contact with the piston. As opposed to the other side which spreads the breaking force nearer the outer side of the pad via the caliper....if that makes sence?

But that pitting is terrible, I would be replacing thoses discs ASAP....

As there vented do you think they could have rusted from the other side?

[Davrav]

I wonder if that was a poor casting.

Would be interesting to see a section through them

[Big Kev]

I wonder if that was a poor casting.

Would be interesting to see a section through them

Dead easy, Dee.....hold them up to the light....? Unless you need car for work on Monday, Goldie, I would VOR until replaced....good wan from Jedi though....looks like they have perished from inside out....?

bIG kEV

[Jamesbelfast]

I take it the discs are the Toyota brand. If so it doesn't surprise me in the least as their quality has diminished to what is barely acceptable.

Pitting as shown in the photo is due to poor quality metal spalling when water droplets hit it when hot.

The rust on the edges is not uncommon on poor quality or poorly designed brake components or on high mileage discs.

Go get yourself a decent set of pads and discs - anything but MrT's rubbish.

The bean counters strike again - lets make more profits at the expense of the poor motorist.

Speaking of quality and lack of use!! My wife drives a 2001 Honda Civic with 60K on the clock and it's still on it original discs. She only drives around 1500 miles per year so being parked up isn't the issue if the quality is there to begin with.

[jedi134]

I do recall problems with discs and pads on your year of rav.......maybe buy some good quality non Toyota discs and pads and see how you get on.

[ormi]

seen loads like this if caught early you can skim them.

[jedi134]

What causes them to look to look like that?

any ideas?

[ormi]

short answer........crap metals...if you need disks go after market

[anchorman]

I take it the discs are the Toyota brand. If so it doesn't surprise me in the least as their quality has diminished to what is barely acceptable.

Pitting as shown in the photo is due to poor quality metal spalling when water droplets hit it when hot.

The rust on the edges is not uncommon on poor quality or poorly designed brake components or on high mileage discs.

Go get yourself a decent set of pads and discs - anything but MrT's rubbish.

The bean counters strike again - lets make more profits at the expense of the poor motorist.

Speaking of quality and lack of use!! My wife drives a 2001 Honda Civic with 60K on the clock and it's still on it original discs. She only drives around 1500 miles per year so being parked up isn't the issue if the quality is there to begin with.

This is a sweeping statement James ;)

In fact the discs that Mr T sell are excellent quality. When assessing disc quality there isn't much to it. Plain old grey cast iron with a brinell hardness of at least 200 and some control over titanium content and the rest is down to machining. In the latter respect that probably accounts for most of the cost as Mr T's discs are ground and not turned.

The problems come with the friction material and the way they deposit (transfer material from the pad to the disc) in some cases. On my last RAV the problem was solved and the discs were in perfect condition. I have also noticed on other Toyota models there is no such problem. Where pads have a high abrasive content they will keep the discs clean - the European manufacturers use lots of abrasive (have a look at the discs on a BMW, Audi or VW, they gleam). The !Removed! are very conscious of black dust and the abrasive content is down but they are coming round to our way of thinking. Good move on their part as our fomulations are about 1/8 of the cost of theirs.

ORMI.

The wear grooves are not untypical but the pitting is.

[Big Kev]

I take it the discs are the Toyota brand. If so it doesn't surprise me in the least as their quality has diminished to what is barely acceptable.

Pitting as shown in the photo is due to poor quality metal spalling when water droplets hit it when hot.

The rust on the edges is not uncommon on poor quality or poorly designed brake components or on high mileage discs.

Go get yourself a decent set of pads and discs - anything but MrT's rubbish.

The bean counters strike again - lets make more profits at the expense of the poor motorist.

Speaking of quality and lack of use!! My wife drives a 2001 Honda Civic with 60K on the clock and it's still on it original discs. She only drives around 1500 miles per year so being parked up isn't the issue if the quality is there to begin with.

This is a sweeping statement James ;)

In fact the discs that Mr T sell are excellent quality. When assessing disc quality there isn't much to it. Plain old grey cast iron with a brinell hardness of at least 200 and some control over titanium content and the rest is down to machining. In the latter respect that probably accounts for most of the cost as Mr T's discs are ground and not turned.

The problems come with the friction material and the way they deposit (transfer material from the pad to the disc) in some cases. On my last RAV the problem was solved and the discs were in perfect condition. I have also noticed on other Toyota models there is no such problem. Where pads have a high abrasive content they will keep the discs clean - the European manufacturers use lots of abrasive (have a look at the discs on a BMW, Audi or VW, they gleam). The japs are very conscious of black dust and the abrasive content is down but they are coming round to our way of thinking. Good move on their part as our fomulations are about 1/8 of the cost of theirs.

ORMI.

The wear grooves are not untypical but the pitting is.

If anybody would like photos of my discs with the Toyota depositing pads, and the way the discs are now with Apec after market pads fitted, just ask.....neighbours are wondering why I lie at side of my car most mornings....I now have front and back shaving mirrors.

Big Kev

[goldgit]

replaced with a set of unipart blue print (Jap produced) discs £60. Pads £30 the originals were Toyota (part numbers still visable) just over an hour to change both sides have dropped a disk in to local toyota dealer with a strong complaint, not holding my breath over them coming back with a guilty plea though

[Guest]

neighbours are wondering why I lie at side of my car most mornings....I now have front and back shaving mirrors.

You must have it really bad in order to have to shave your back most mornings.

Gus