For anyone doing the brakes on their car, look into ceramic brake pads. I’ve recently replaced mine and used the ones from ATE and it’s actually insane how much less brake dust these give off. My front wheels used to be absolutely coated in black dust after long road trips but now there is pretty much zero buildup. They are only like 1-2 Euros more expensive than the regular ones. It’s a total no-brainer.
Aren’t they harder on the rotors though? The whole idea behind brake pads is they’re significantly softer than the rotor, so you can go through many pads before changing the rotors.
No, a so called “transfer film” forms on the surface of the disk that reduces the overall wear and resulting brake dust.
Though it should be noted that you shouldn’t just slap on ceramic pads without also changing to new rotors as the pattern of wear from the pads is different.
Does it matter - I’ve never seen rotors not need replacing when doing a breakjob. Once I was able to resurface the existing rotors but it cost almost as much as new rotors and broght them to the minimuns.
If you grind your brakes all the way down to the backing plate then yeah you’re going to mess up the rotors. If you change your brakes around 2mm when it starts hitting the squealer tab you can usually get 3 or even 4 brake changes out of a set of rotors though. It’s not a sure thing but it’s true more often than it isn’t.
Do you live somewhere that you get a lot of snow and therefore a lot of salt in the roads? Rotors can rust and that can make you need to change them more often.
If you don’t live somewhere that rust problems are common though, you might want to have somebody inspect your calipers, or try a new mechanic. You really shouldn’t be having to change rotors every time. That’s a lot of money.
I swap my body panels more often than my rotors (thanks, salt). You should not be replacing the rotors on every pad replacement even in salty conditions.
You need to refinish them on every pad change, and that is the same cost as a new rotor. You can sometimes get by with putting pads on, but if you measure the rotors they are likely out of spec. (not many home shops have a proper micrometer to measure with)
My Nissan needed new rotors every time the brakes starting squeaking, about every 6 months. I’ve never had any other car need the rotors replaced, maybe because I tend to drive smaller cars.
If you mean electric vehicles, they are much better at engine braking than fossil fuel vehicles, because the braking power can be precisely applied through the motor acting as a generator. In Toyota hybrids as well.
The number of gears doesn’t really matter in this case.
Even a gas engine doesiengine breaking pretty good. Not as controllable as a electric but still a major difference. Diesels don’t do much though (unless you have a ‘jake break’ - which I’ve never seen in less than a semi)
In my experience diesels brake better than petrol engines. Maybe it’s because of their longer stroke and better compression. But in any case a manual transmission is best.
That is not expected - while a diesel has more compression, that compression matters zero (other than friction losses - which might be what you are feeling) since all the energy lost in compression is returned in the next part of the cycle when the energy is returned. Unless you have a “jake brakes” which opens the exhaust valve at the top of the compression stroke thus venting the energy to the atmosphere instead of returning it to the power stroke.
A gas engine has a throttle plate which means when the engine is coasting very little air goes into the cylinder and so on the power stroke the low pressure in the cylinder is fighting against the higher air pressure in the engine.
I agree manual transmissions are best, but I’m a minority (I live in the US, other parts of the world prefer manuals) and so I can rarely find them. That said, an automatic in low gear gives plenty of engine braking.
Isn’t it the case that diesel engines continue to compress air while petrols don’t? This plus the significantly longer stroke might account for some of the difference. Yes the air is decompressed right afterwards but significant amounts of work must be lost as heat.
I don’t know what to say. It’s just my personal experience. While driving different cars the diesels always braked much more, and at lower RPMs. Coasting down an incline, put the diesel in 3rd, it will spin up to 2000 then go down to 1600 and stay there, braking the car 10-15 km/h. The equivalent petrol will spin up to 3000 and stay there, and not reduce the car’s speed, just keep it from accelerating. Something like that happened across many different cars and engine displacements. Maybe it’s because the petrols go down to as little as 1L of displacement and 3 cylinders while the smallest diesels are still at 1.6L and 4. Or it’s because the diesels are always turbocharged, while the petrols are sometimes naturally aspirated.
American here, thought those were the standard? I’m pretty ignorant with auto mechanics, though I can change break pads. If someone asked me what they’re made of, “I dunno. Ceramic of some kind.”
Newer vehicles typically have ceramic stock (well at least my newest car did), but I think “organic” were standard until relatively recently. There’s pros and cons to each.
For anyone doing the brakes on their car, look into ceramic brake pads. I’ve recently replaced mine and used the ones from ATE and it’s actually insane how much less brake dust these give off. My front wheels used to be absolutely coated in black dust after long road trips but now there is pretty much zero buildup. They are only like 1-2 Euros more expensive than the regular ones. It’s a total no-brainer.
Aren’t they harder on the rotors though? The whole idea behind brake pads is they’re significantly softer than the rotor, so you can go through many pads before changing the rotors.
No, a so called “transfer film” forms on the surface of the disk that reduces the overall wear and resulting brake dust.
Though it should be noted that you shouldn’t just slap on ceramic pads without also changing to new rotors as the pattern of wear from the pads is different.
Does it matter - I’ve never seen rotors not need replacing when doing a breakjob. Once I was able to resurface the existing rotors but it cost almost as much as new rotors and broght them to the minimuns.
Wat. I replaced the rotors once in my life, on a car that had like 400000km on it
If you grind your brakes all the way down to the backing plate then yeah you’re going to mess up the rotors. If you change your brakes around 2mm when it starts hitting the squealer tab you can usually get 3 or even 4 brake changes out of a set of rotors though. It’s not a sure thing but it’s true more often than it isn’t.
your experinece is different than mine I guess.
Do you live somewhere that you get a lot of snow and therefore a lot of salt in the roads? Rotors can rust and that can make you need to change them more often.
If you don’t live somewhere that rust problems are common though, you might want to have somebody inspect your calipers, or try a new mechanic. You really shouldn’t be having to change rotors every time. That’s a lot of money.
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I do live in such a place. That may well be a factor.
I swap my body panels more often than my rotors (thanks, salt). You should not be replacing the rotors on every pad replacement even in salty conditions.
You need to refinish them on every pad change, and that is the same cost as a new rotor. You can sometimes get by with putting pads on, but if you measure the rotors they are likely out of spec. (not many home shops have a proper micrometer to measure with)
My Nissan needed new rotors every time the brakes starting squeaking, about every 6 months. I’ve never had any other car need the rotors replaced, maybe because I tend to drive smaller cars.
Your should try coasting more, looking further ahead than the car in front of your bumper and finessing the brakes, works even better than ceramic.
Ceramic pads are pretty great though
Also engine braking
Ha! What are gears for in a car?
I agree, if you’ve got 'em its far better.
If you mean electric vehicles, they are much better at engine braking than fossil fuel vehicles, because the braking power can be precisely applied through the motor acting as a generator. In Toyota hybrids as well. The number of gears doesn’t really matter in this case.
Even a gas engine doesiengine breaking pretty good. Not as controllable as a electric but still a major difference. Diesels don’t do much though (unless you have a ‘jake break’ - which I’ve never seen in less than a semi)
In my experience diesels brake better than petrol engines. Maybe it’s because of their longer stroke and better compression. But in any case a manual transmission is best.
That is not expected - while a diesel has more compression, that compression matters zero (other than friction losses - which might be what you are feeling) since all the energy lost in compression is returned in the next part of the cycle when the energy is returned. Unless you have a “jake brakes” which opens the exhaust valve at the top of the compression stroke thus venting the energy to the atmosphere instead of returning it to the power stroke.
A gas engine has a throttle plate which means when the engine is coasting very little air goes into the cylinder and so on the power stroke the low pressure in the cylinder is fighting against the higher air pressure in the engine.
I agree manual transmissions are best, but I’m a minority (I live in the US, other parts of the world prefer manuals) and so I can rarely find them. That said, an automatic in low gear gives plenty of engine braking.
Isn’t it the case that diesel engines continue to compress air while petrols don’t? This plus the significantly longer stroke might account for some of the difference. Yes the air is decompressed right afterwards but significant amounts of work must be lost as heat.
I don’t know what to say. It’s just my personal experience. While driving different cars the diesels always braked much more, and at lower RPMs. Coasting down an incline, put the diesel in 3rd, it will spin up to 2000 then go down to 1600 and stay there, braking the car 10-15 km/h. The equivalent petrol will spin up to 3000 and stay there, and not reduce the car’s speed, just keep it from accelerating. Something like that happened across many different cars and engine displacements. Maybe it’s because the petrols go down to as little as 1L of displacement and 3 cylinders while the smallest diesels are still at 1.6L and 4. Or it’s because the diesels are always turbocharged, while the petrols are sometimes naturally aspirated.
I often drive through pretty mountainous regions, coasting or even downshifting won’t help much unfortunately.
I live in the mountains, they do help.
Yupp, can confirm. Been using them since 2011 in my cars and they are awesome!
American here, thought those were the standard? I’m pretty ignorant with auto mechanics, though I can change break pads. If someone asked me what they’re made of, “I dunno. Ceramic of some kind.”
Most are made out of mixtures of metals like copper, iron and steel. Ceramic brakes are more prone to fading though.
The cheapest ones that most people default to are usually barely glued together carbon powder. But good mechanics definitely carry and use ceramic
Newer vehicles typically have ceramic stock (well at least my newest car did), but I think “organic” were standard until relatively recently. There’s pros and cons to each.