brake help

[Crazyjim]

Hope this is the correct section . But of help advice needed . I have not long had my 2013 Mercedes C220 diesel . Had couple of small issues cheap tyres now resolved knocking from front . Now resolved. I don’t drive cars hard but today I was running late for work no excuse I drove faster than I usually do but within the speed limit officer . Anyway I had to brake and at low speeds my brakes feel fine not much pedal travel but my brakes faded today and thought something not quite right had a look and there is new front disks and pads fitted and new rear pads but was thinking if pedal is solid could there be air in system thoughts please because brakes are a vital part for me

 

[Bellow]

Brakes will only fade after some amount of abuse - and smell. (Unless they (all 4?!!!) are binding and thus pre-heated).
Air in the system makes the pedal spongy.

 

[Crazyjim]

Ok thanks . Wasn’t really heavy braking so to me shouldn’t be fading like that . And smelling yes I did smell burning wonder what garage has done wrong fitting the new disks and pads . Brake bind I didn’t think they were binding but will check thanks

 

[markjay]

Brakes will only fade after some amount of abuse - and smell. (Unless they (all 4?!!!) are binding and thus pre-heated).
Air in the system makes the pedal spongy.

As above.

In over 40 years of motoring, I have only experienced brake fade (i.e., otherwise perfectly-serviceable brakes becoming ineffective simply due to overheating), when I was in my 20's, on a modified car... next thing I upgraded the brakes (Tarox grooved discs and matching pads), though it took a few years before I have upgraded my driving to 'like any normal sane person would drive' and had no need for upgraded brakes...

But my point is that you really need to abuse the car before it suffers brake fade. And yes the feeling (as far as I can remember it) was of a normal hard brake pedal, but very little braking taking place, more like what you would get if you applied the parking brake instead.

But before condemning the discs and pads as poor-quality cheap cr@p... are the discs and pads very new? They may need to bed in. Manufactures usually recommend 200Km (120 miles) of moderate braking with new discs and pads.

 

[Crazyjim]

Interesting point mark Jae . The disks on front and all pads are brand new . I have done 250 miles since buying the car all non motorway miles . Except for today when I was running late so went 2 work on motorway

 

[Petrol Pete]

Brake fade on a modern road car driven normally on the road does not exist, especially on a 2013 C220 diesel. Something must be wrong with the brake system in your car.

 

[Mattns]

I agree, probably need bedding in.

I too have only experienced brake fade in the 70's while descending a very steep long hill around a mile on a B road and preferring to brake rather than use 1st gear, by the time I got to the bottom there was no braking affect, talk about scary, I'm not sure whether the smell was from the car or my underwear

 

[rf065]

Interesting point mark Jae . The disks on front and all pads are brand new . I have done 250 miles since buying the car all non motorway miles . Except for today when I was running late so went 2 work on motorway

How many miles since fitting new brakes would be more relevant, they need to bed in before working 100%, your garage should have warned you to take it easy until then?

 

[Bellow]

Ok thanks . Wasn’t really heavy braking so to me shouldn’t be fading like that . And smelling yes I did smell burning wonder what garage has done wrong fitting the new disks and pads . Brake bind I didn’t think they were binding but will check thanks

If you smelled burning then it's a heat (not a bedding in) issue. My suspicion is the new pads have been crammed into sticky calipers and binding/rubbing is causing the brakes to be hot before they are even applied.
That it deprives you of braking on all wheels is odd though. As is the event occurring after a motorway run (motorway use being kinder to brakes than a B-road) but there can be issues re rubbing/highspots that are worst under motorway conditions - and the possibility of a disc (or more) not being true on its hub (not uncommon after replacement) is also a possibility.

The brakes need to be re-examined for further clues.

 

[saff]

I agree, probably need bedding in.

I too have only experienced brake fade in the 70's while descending a very steep long hill around a mile on a B road and preferring to brake rather than use 1st gear, by the time I got to the bottom there was no braking affect, talk about scary, I'm not sure whether the smell was from the car or my underwear

If your 5h1t smells like overheated brakes I'd go and see your GP

 

[Crazyjim]

Sorted today bellow top man. Had 2 put Oe pads . The pads on the rear were sticking in the carriers so ordered oe ones and they fitted in without jamming in carrier .also pads I took out were very glazed can only assume the were burned fitted new ones and car feels smooth and pedal deals better thanks for everybody’s help.