Does anyone else have rear discs that look like this, my car is April 2017 and has done 15000 Miles, I've never seen discs looking like this after 18 months in 20 years or so of driving, The car never goes more than a few days without being driven So I'm a bit miffed, Glyn Hopkin seem to think they're fine. Quite frankly I think these are a dodgy batch of discs or pads.
Technical Rear Brake Discs
- Thread starter Alboreto
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Technical Rear Brake Discs
twobigdogs
Member
My front discs needed replacing at 36000 miles very badly lipped and pads down to 2mm and no warning light! Rear discs look unworn though. This on a 2015 car. I was not impressed.
Just approaching 36,000 miles in a 2015 car, still got original discs and pads all round. At service last December the front pads were only 10% worn according to the dealer, but I bet they'll want to change them this year. Rear pads and discs absolutely fine
The general consensus is that discs are consumables nowadays and made with varying grades of steel, i often see similar but when you can replace cheaply I would only be concerned with an even contact patch the full size of the pad expected to provide the fiction to stop. You can wash your car and 20 mins later a full layer of oxidation can be present.
Nello
Established member
I think you will find you have the electronic handbrake acting on the rear calipers for that! I'm as guilty as anyone for actuating when the car is not completely stationary.........
Why not leave it in the automatic mode, like I have?
If you're wearing the pads down to 2mm in 36,000 miles then you must be beating the brakes up a bit.
Do you do a lot of town driving?The 500X is not a heavy beast but the brakes are also not as big as they might be, so they work hard for a living and some TLC will make them last a lot longer.
But they're not a "lifetime use" item. Modern pads are more agressive than in the old days when they contained asbestos. Without the asbestos (kills people who insist on breathing it in, apparently) the manufacturers add sintered metal. This makes the pad almost as hard as the disc, so the disc will wear out much more quickly than you might expect.
2mm won't give you a warning..The light comes on when the sensor becomes earthed against the disc, so the pad will be 1mm/pretty much down to the backing plate before that happens. You could also check that the cable has not been snared on something and become cut or disconnected too... it sometime happens... but so far, apart from the wear rate you get, it sounds okay to me.. no reason to be not impressed.
Ralf S.
Assuming that the discs and pads are made by someone who makes brakes and pads for a living (and not by Fiat, just to annoy their customers) then you would have to assume that the pads and discs are consistent throughout their surface... and so the scoring you get is a result of the rear caliper design/setup.
You will get grit and rust on the discs (you don't need to go to a beach to find grit) and that could cause scoring... but the real "problem" is that the rear calipers don't act on the rear discs with much force compared to the front... so it exaggerates the areas where there is more pressure on the disc compared to where there isn't, so you get a groove effect.
As above, it's not an actual problem. I've seen it on lots of my own cars and changing the discs and pads for different brands makes no difference, so it's not the pads or the discs.
The front discs are less affected by grooving since they transmit 80% of the braking effort and that tends to even out any grit or grooves. The "peaks" of any grooves would get more pressure until they are rubbed away.
If you have a brake compensator on the X then it may be worth checking the adjustment to make sure the rear brakes are being used as intended. If the compensator becomes lazy (pre-electric brakes it is/was a mechanical device held under a spring tension) then the rear circuit gets less fluid/brake force and that exagerates the "light skimming" appearance rather than the fully clean/pulverised smooth effect as you see on the front.
If you never carry a load of rear passengers then it may be worth putting 10 bags of wet sand in the boot and going for a drive. The lower rear suspension should make the brake compensator send more force to the rear.
If you wash your car and the discs get a sheen of rust on them (being iron.. it's not a "Fiat Feature") then you go for a drive of 1 mile and the discs are shiny metal all across their surface (+/- the inner/outer few millimetres) then they're okay.
Ralf S.
Ralf S.
This is a good point but I use the handbrake manually, only on the rare occasion if I let it release by itself and you lift the clutch a bit quick it stays engaged but would that cause scoring like that
The Panda Nut
Nutty about Pandas Infected by Panda virus and OPD
I think they are correct. They look normal.
They do look like lack of use / gentle driving. If it were me I would clean the discs with emery paper and remove the pads and clean them too. Get your mother in law in the back and go out to lunch. The weight in the back will probably shine up the discs without other works. My discs look like this after washing the car and parking up for a day or two. They shine up after a drive.
Fiat discs seem to surface rust easily but its not something to worry about as the spec is designed to stop the car, not to resist rust necessarily. New discs are aluminised to control rust on non wearing surfaces. The discs are made by Ferodo and a look at their web site should set your mind at rest on any quality issues.
They do look like lack of use / gentle driving. If it were me I would clean the discs with emery paper and remove the pads and clean them too. Get your mother in law in the back and go out to lunch. The weight in the back will probably shine up the discs without other works. My discs look like this after washing the car and parking up for a day or two. They shine up after a drive.
Fiat discs seem to surface rust easily but its not something to worry about as the spec is designed to stop the car, not to resist rust necessarily. New discs are aluminised to control rust on non wearing surfaces. The discs are made by Ferodo and a look at their web site should set your mind at rest on any quality issues.
twobigdogs
Member
If you're wearing the pads down to 2mm in 36,000 miles then you must be beating the brakes up a bit.
The 500X is not a heavy beast but the brakes are also not as big as they might be, so they work hard for a living and some TLC will make them last a lot longer.
But they're not a "lifetime use" item. Modern pads are more agressive than in the old days when they contained asbestos. Without the asbestos (kills people who insist on breathing it in, apparently) the manufacturers add sintered metal. This makes the pad almost as hard as the disc, so the disc will wear out much more quickly than you might expect.
2mm won't give you a warning..The light comes on when the sensor becomes earthed against the disc, so the pad will be 1mm/pretty much down to the backing plate before that happens. You could also check that the cable has not been snared on something and become cut or disconnected too... it sometime happens... but so far, apart from the wear rate you get, it sounds okay to me.. no reason to be not impressed.
Ralf S.
I drive a mix of driving town/motorway etc and all of the many cars I have owned I have never worn out a set of front discs in 36000miles! I’ve had BMW,Renault,Ford,Vauxhall,Mazda,
Fiat some new and some were autos. The Renaults were always breaking down but even they never wore out front discs. My BMW auto coupe went to 85000miles on front discs! As I said not impressed with this Fiat.
Its not a Fiat, its a Jeep.
There are a lot of brake problems reported on the Forums and the like.
D
There are a lot of brake problems reported on the Forums and the like.
D
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Nello
Established member
I do mate in as much as I let it Auto release however I have been known to activate the handbrake on before completely stopping.
Nello
Established member
err.......the 500X is built in Melfi (as is the Jeep!) and its based on the Fiat 4x4 Small architecture first used on the Grande Punto - In what way is it a Jeep? I think its the other way around.........
I'm not convinced that the Fiat/Jeep is relevant..
The brakes are made by Ferodo and the calipers are probably Valeo or Bosch... They don't know whether they are fitted to Fiat, a Jeep or any other Euro-brand.
They just looks like they need a bit more of a workout (a heavy load in the back is the only way) or a compensator adjustment (if there is a mechanical/adjustable one fitted).
Ralf S.
The brakes are made by Ferodo and the calipers are probably Valeo or Bosch... They don't know whether they are fitted to Fiat, a Jeep or any other Euro-brand.
They just looks like they need a bit more of a workout (a heavy load in the back is the only way) or a compensator adjustment (if there is a mechanical/adjustable one fitted).
Ralf S.
How wrong could I be? Just 1,500 miles later, service done, pads and discs all round. Front discs down to the minimum, rear discs pitted and scored. Ouch
