Rear Disc crack. How??!

[Tom_E]

Hi All,

I've just had two new tyres fitted on the rear, and this was discovered in the process:

How does this happen? Is this a known issue for OEM Renault Discs? My rear's had around 20k on them.

Cheers.

 

[Jonny1*2]

Binding pads maybe, too much heat. Or just a crap batch

 

[Gregor11]

Mate those discs are scored in a big way! They haven't been wearing correctly on the disc, there is a substansion outer mark where the pads haven't been in contact with the disc, I reckon your caliper is dragging/seized and it's got to hot!

 

[Jonny1*2]

Mate those discs are scored in a big way! They haven't been wearing correctly on the disc, there is a substansion outer mark where the pads haven't been in contact with the disc, I reckon your caliper is dragging/seized and it's got to hot!

My rear wear is like that mate :S

 

[Clart]

My rears are worse than that apart from the crack. Only about 20k old too and they are fcuked.

 

[Tom_E]

not good.

How can i tell if my Caliper is fucked? if i need to replace that also, how much are they from Renault? For the record the disc in question is the passenger rear. Driver side looks fine.

 

[Gregor11]

My rear wear is like that mate :S

Take them apart mate, clean the sliders and work the caliper piston in and out, moderation on copper slip, that in my opinion is a heavily worn disc! The rears don't do a mass amount, even less on the cup version, so they tend to partially seize.

 

[Gregor11]

not good.

How can i tell if my Caliper is fucked? if i need to replace that also, how much are they from Renault? For the record the disc in question is the passenger rear. Driver side looks fine.

Passenger rear is the furthest caliper from the master cylinder so in effect gets the least amount of brake pressure! You'll know if the caliper is seized or not when you come to push the piston back in, the harder it is, the more seized it is!

 

[cupoftea172]

Had that exact thing happen on my cup after a few miles as the caliper had seized and overheated the disc! the disc had turned a nice shade of light blue from the heat, rebuilt the calipers with new discs and pads and all was well again.

 

[Tom_E]

Passenger rear is the furthest caliper from the master cylinder so in effect gets the least amount of brake pressure! You'll know if the caliper is seized or not when you come to push the piston back in, the harder it is, the more seized it is!

Thanks mate.

I've already got a pair or rear discs and pads on order, so when i go to put them on (seems a piece of piss) ill investigate further.

I take it driving really isnt a option until i replace them?

 

[Gregor11]

I wouldn't drive it mate in case the disc actually brakes and could potentially lock up the wheel

 

[Tom_E]

thought as much! god knows how long i've been driving like this, normaly good at checking things. Fail by me!

 

[Gregor11]

thought as much! god knows how long i've been driving like this, normaly good at checking things. Fail by me!

Easy done mate! At least you spotted it now!

 

[Fred@BTM]

knackered caliper, seen it loads of time

 

[Jonny1*2]

out of curiosity, what grease should be used in the sliders? is copper ok? I've been thinking about stripping the calipers for a while now.

 

[Gregor11]

copper grease is fine mate, not to much though, just a liberal coating!!

 

[Jonny1*2]

copper grease is fine mate, not to much though, just a liberal coating!!

Cheers mate