Hypermiling and brake wear (or lack thereof)
 

I started hypermiling my 2008 Kia Rondo three months ago, and I really like the 25% boost in fuel economy. Coasting to lights and keeping speed down on rural roads / highways has really helped.

One thing I noticed real quick is that I use my brakes MUCH less than I did prior to hypermiling. I'm curious--what's the going rate among you hypermilers out there in terms of brake life, either in wear or miles between replacement?

MY rebuilt VX had 0ver 50% front pads left at 65k miles. Thinking about it, I don't remember replacing front pads in a very long time but I typically don't keep cars until they fall apart. I did replace them in my Suzuki GZ 250 but it was probably used as a training bike for the first couple k miles.

regards
mech

big problem for me
 

Rusty brake rotors have been a recurring problem for me. My Firefly (Metro) is on its 3rd set of rotors, with ~37k km / 23k miles on the clock.

It's a combination of two things: (1) very light brake use, plus (2) low distance driven per year. The car regularly sits for a week or 2 between drives, and then when I do drive it, I may not use the brakes aggressively enough to shine up the braking surface again. Once the corrosion gets past a certain point, the pads won't clean it off.

The solution for this situation is to keep an eye on the rotor surface and remember to do some intentionally harder brake applications once in a while to keep the rotors from becoming a problem.

Also the car is parked outside for half the year, which doesn't help (rotors more exposed to the weather).

The brake pads/shoes, on the other hand, will probably last the life of the car!

(Rusty rotors are possibly even a bigger problem on my winter beater 2004 Prius because now most of my already typically "light" braking is of the regenerative kind, so there's even less friction braking compared to the Firefly.)

My brake pads were about 50% at 90,000 miles. But I make 3 downhill stops each day, plus one downhill 55 MPH to 30 MPH hard deceleration every week.

No rust, though.

I normally get 150,000 miles on my front brakes and over 300,000 miles on my rear brakes.

All the brake parts on my '94 are OEM except for the hard lines which rust away from the outside in, thank you very much salt trucks! :mad:

Lessee, the last time I did brakes on the truck was...hmm.

2010? 2008? Around there. Did it myself. Didn't touch the rears, they're fine.

Think "every time you brake, it's a mistake". I read somewhere about over 100 k miles on OE Prius tires.

regards
mech

my front brake pad were used at 50% after 25k miles of normal driving and 55k miles of hypermiled driving.

I've only replaced the front brakes on the ZX2 once in the 83,500 miles I have driven it. That is only due to not be a hypermiler for the first 25,000 miles of driving, and the front brakes were ~30-40% when I got the car.

They were replaced around 55,000 miles ago and still look new. The rears will be replaced soon as they probably have over 100,000 miles on them and sound bad when I have to brake hard.

Closing in on 150,000 miles with my XFE, when I installed the winter tires a few week ago the front pads look like 3/4 of thickness left. Doubt I'll ever take a drum off unless a wheel cylinder starts leaking. (first 26,000 on the XFE were by someone else).

Previous 03 Malibu and the XFE rotors rust fast if left outside wet, just over a weekend they'll grind the first few stops.

I checked out the pads when I put the moon discs on Ron Burgundy and they looked like they were around 65-70% (due to the previous owner), so I figure they'll last the life of the car, or at least the life of the car as long as I own it.

At 70,000 miles, my Mustang's front pads are ~10 mm and rear pads are ~ 8 mm.
Front pads on my F-250 are over 10 mm after 105 K miles (since replacement).

Looking at the records, as far as I can tell, the previous owner of my car had his original brake pads in the front replaced at about 150,000 miles. The original rotors are still on the car.

The original rotors are on my car at 270k miles. I've only replaced pads in that time. However, I had a fast stop the other day and noticed that the rotors are wobbly. Guess it's time to replace them.

Interesting topic. Never really gave it much thought. I suspect the folks that have rotors that rot away live in flat places. I can see how someone in the flat parts of the midwest where they also have harsh winters would have this problem. No real worries here in hilly New England. Even the best hypermiler has to do a good bit of braking here.

I do wonder if for hybrids it might make sense to look at going back to the stone age with 4 wheel drum brakes which due to their design are less likely to rust. There is no need for the added cooling abilities if regen is doing the majority of the work.

This particular hybrid has aluminum drums in the rear, and aluminum calipers in the front. I believe the only steel bits are the rotors in the front and the brake lines. This is what they look like at age 15:

http://i1072.photobucket.com/albums/...pshshamuxa.jpg

http://i1072.photobucket.com/albums/...psr2q3x0ca.jpg

My Pontiac G6 had no brake pad issues. However, the coast to my driveway resulted in some corners being taken a little faster than normal. It caused two of my wheel hub assembly bearings to fail prematurely. Pontiac was kind enough to fix one for free. The other was too dangerous to risk driving to the dealership and had to be fixed locally...it cost me $300.

Doubt very much hypermiling had anything to do with it.

You don't see a correlation between high speed cornering and increased wheel bearing wear?

I'd say your wheel bearings were going to die regardless. I think you're the first on this forum to make that link. 99% of the way we drive increases component life. Lower overall speeds and reduced braking are going to help wheel bearing life. It's not unknown for GM/Ford unit bearings to fail at low miles in any case.

Where appropriate I always corner 'hard' and my cars see weekend blasts in the hills and track use, never killed a bearing yet. 60k miles is about what you can expect from non-servicable unit bearings, done are the days when with appropriate maintenance the bearings would last the life of the car.

I was well under 60K...closer to 40K and I lost both front wheel bearings. I had never had bearings fail that fast in anything. I attributed the failure to the cars weight and the turning speeds. My VX didn't have any issues with it, but it was a feather-weight compared to the G6.

A friend of mine drove one of those for a good while too. I think hers went out around 35-40k and had to be replaced. Maybe it's an issue in that model.