Brake pad wear (vehicle, manual transmission, van, engine)
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
I would think that for the most part it's all about the energy absorbed by the pad and rotor. Therefore, I bet that from any given speed, slamming on the brakes and easing on the brakes to a stop results in ABOUT the same pad wear.
In reality, those people who slam on the brakes are likely the same people who are on the gas for longer, so they end up stopping from a higher speed, therefore needing to absorb more energy. Nobody coasts as long as they can, only to slam on the brakes at the last minute.
I would think that for the most part it's all about the energy absorbed by the pad and rotor. Therefore, I bet that from any given speed, slamming on the brakes and easing on the brakes to a stop results in ABOUT the same pad wear.
Nope.
You are correct to think about the total energy involved, but what you are neglecting to think about is time elapsed and heat generated.
Easing the brakes to a stop allows the rotor to dissipate heat while the rotor is still turning. Temperatures do not get anywhere near the level they do when slamming on the brakes.
Greater heat = greater friction = greater wear.
For people who generally drive like an old lady, it's not uncommon for their brake pads to last 100k or more, especially on cars with large, oversize calipers and pads. If you ever find an elderly Corvette owner who babies their car, I bet they've never changed the pads.
My mother's old S class had 55k on it when she traded it in. That's not a high number of miles, but she only keeps her cars for about 4-5 years and 30-40k, she doesn't drive much.
At 55k, the brake pads looked almost brand new. Extremely low amount of wear, tons of material left.
I would think that for the most part it's all about the energy absorbed by the pad and rotor. Therefore, I bet that from any given speed, slamming on the brakes and easing on the brakes to a stop results in ABOUT the same pad wear.
In reality, those people who slam on the brakes are likely the same people who are on the gas for longer, so they end up stopping from a higher speed, therefore needing to absorb more energy. Nobody coasts as long as they can, only to slam on the brakes at the last minute.
With brake pads, it's *all* about the material used in the pad, and there is no "standard", nor is there any oversight at all. I can literally stick bubble-gum on a brake pad backing plate and call it "super awesome brake pads", and you could sue me if you got in an accident because the pads were inferior, but no one in the government actually checks pads to see if what you're paying for is what is actually in the box.
A brake pad can stop great, but leave your wheels covered in dust - or stop great - and wear out super-quick, or stop poorly & last nearly forever. It's all about the company selling the pads & how much they value both their reputation & the business of installers/service facilities <--- who buy pads by the pallet.
A quality pad from a respected company like Raybestos, Bendix or Wagner will probably last a good while, even in severe conditions, but with rampant off-shoring of manufacturing, you're relying on the name on the box for quality control, and even the big-guys get zinged periodically with junk. The parts stores that focus on selling to shops and installers (like NAPA & CarQuest) usually have decent quality "store brand" pads, and places like RockAuto let you pick through the parts catalogs to find the "super-awesome" pads from several different manufacturers & pick the brand you trust, along with the grade of pad you want.
Personally, I've been buying my pads from RockAuto lately & while I don't buy the most expensive pads - I do pick a real brand-name & something a couple "grades" above the cheapies.
Quite often there's an option for a "police-taxi" pad material & while it can be a little dusty & noisy, it's also *usually* a pad that wears quite well - which is more important to me than brake dust or a slight squeak on light application..
I have a 2008 Expedition with 70K miles on it. It is my daily driver and I use it to haul everything. I do highway and stop and go driving. My rear brake pads had to be replaced at 30K miles but my front pads are original and are only about halfway worn.
I thought about the time elapsed and heat generated, but I still doubt that that makes near as much of a difference as the fact that those who wait until the last minute to brake are the same people who are on the gas longer and therefore have a need to scrub off more speed.
I suppose it would depend on the characteristics of the friction material. Do its characteristics change drastically with temperature? Were they already hot before the stop? Etc...
And we can talk about pad quality all we want, but as I understood it the question was regarding any one given pad. Of course one pad will wear differently than another no matter how you drive them. The question as I understood it was with the same pads, which wears quicker, a set subjected to quicker stops or a set subjected to granny stops.
While we're on the topic, I'll never again buy aftermarket brake pads...unless for some reason I get into racing and I don't care about squeal, longevity, etc... The amount of testing the automotive manufacturers put into testing each pad for any model of car is enormous. A pad that performs great on one car can squeal like mad on another. Just because Joe Blow Aftermarket Manufacturer can make a pad that fits and gets the car to stop doesn't mean it won't squeal, wear quicker, produce a ton of dust, and stand up to abuse.
The question as I understood it was with the same pads, which wears quicker, a set subjected to quicker stops or a set subjected to granny stops.
Yes, and the answer is that pads will wear faster if subjected to quicker (and thus harder and with more pedal pressure) stops.
Think about it this way... If a car was going 100mph on a flat surface, and then you get off the gas... That car is going to eventually stop. Why would it stop? Rolling resistance from the tires, the air resistance/drag from the car, mechanical friction from the transmission, axles, driveshaft, etc. That car is going to eventually coast to a stop, with no brakes at all applied. So you have all those factors involved in getting a car to stop, slowly.
By jamming on the brakes forcefully, you aren't relying on any of those things to slow the car down, just the brakes. Of course the pads will wear a lot quicker, they have to do extra work.
Now on a FWD the fronts always were out twice as fast as the rear, because all the weight is in the front ther is no rear end on a FWD. and certain cars and trucks brakes were out faster than most. GM had their fair of brake problems to the point they went back to using drum brakes again on their pickups.
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.
Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
