MOT Advisory: Service brake fluctuating Offside Front

[AndrueC]

Can anyone elaborate on this please? A Google search finds people saying 'don't worry about it' but I'd like to understand it better.

For what it's worth I'm a very, very light user of the brakes. Almost the only time I use them is when stopping. To me using the brakes to adjust speed is the sign of a poor driver.

Just found the list of advisories and it's classed as a major. But the actual text on the sheet says 'but not excessively'. So it's a major issue but not excessive? What am I supposed to make of that?

[TonyHSD]

Well, that what happens if you don’t use them. They get rusty and then cause trouble. I think a brake service it’s just the right time. No need to replace anything, just dismantle, clean, lube the pins and put back in everything together. If the disc are scorched can do with sandpaper for wood or wire brush. Pads wire brush them too and brake cleaner spray . Then gentle for  the first few stops and then you gonna have new like brakes. But you have to use them more. Best places to clean and polish the discs are coming off the motorway, do a late slow downs and the brakes will be nice and clean, no mot advisories too. 👍 

Btw I had to change twice full sets of discs and pads became the car was not used enough and everything  was rusted beyond salvage. Since then 100k miles and I only need a rear ones eventually later this summer. Fronts will be good for another 30-40k miles.  
Here very interesting video to explain how the calliper works and btw looks exactly like on Toyota. If one or both pins are dry the outer pad can not press enough to the disc and cause fluctuation and uneven pad wear plus the disc surface can not be cleaned properly. 

 

[Derek.w]

Can you take a photo of the front rotor disks I suspect its just rust on them .

A quiet road and apply some stopping power to clean the rust off or even a light rub with emery cloth can help.

After all that its a good idea to clean brake calipers at least the slider pins or it pads are worn replace them but then you need to push the pistons back front ones rear ones you need to enter service mode if its a electronic handbrake to relise handbrake and the piston screws back in with a tool.

[AndrueC]

That makes sense. I also park the car in my garage and I've once or twice had a hesitation then a clunk as I reverse out. I've been told that's probably rust build up.

I'll have to remember to give them a work out now and again.

[Don Mac]

59 minutes ago, AndrueC said:

That makes sense. I also park the car in my garage and I've once or twice had a hesitation then a clunk as I reverse out. I've been told that's probably rust build up.

I'll have to remember to give them a work out now and again.

You should be able to see the discs through the wheels. If they don't look nice & shiny after a drive you really haven't used the brakes! 

If the discs aren't polished (swept) across their entire width, they are inconsistent from wheel to wheel or there is excessive pitting/scoring on them you may need to do a bit more than stand on the pedal to fix them.

The hesitation & clunk sounds like the parking brake sticking a little. That is a separate system from the service (foot) brake and only works on the rear wheels. If it only does this occasionally I don't think that's anything to worry about. Parking the car for a bit longer than usual in damp weather could be sufficient to cause this. (don't try using the parking brake whilst you're moving to sort this one out...)

[oldcodger]

Long long ago, when doing a service some garages would Skim the discs for you if they were not badly worn / too thin, which yours should not be.

If the above methods to remove the rust do not work , check if your local dealer has an in situ skimming machine and the cost which should be a lot less than replacing the discs, when done as part of a full service.

 

 

[Dylanfan]

22 hours ago, oldcodger said:

Long long ago, when doing a service some garages would Skim the discs for you if they were not badly worn / too thin, which yours should not be.

If the above methods to remove the rust do not work , check if your local dealer has an in situ skimming machine and the cost which should be a lot less than replacing the discs, when done as part of a full service.

 

 

Skimmed many discs, drums & cylinder heads in my time. Any local engineers will do that, discs shouldn’t cost a lot, but a good clean up should do the trick.