Cripes, well I've *never* seen this before...

[Wayne 962]

I've been working around cars and writing books, etc, for quite a few years, and today I saw something that I have never seen before, and I still cannot figure out how it happened.

Background:

A few years ago, I owned a 2WD Suburban. We took it up to the mountains at Christmas and it snowed and it was a disaster. Shortly thereafter, I bought a 4WD Suburban, a 2500 (the big one). I wanted one with low miles, so I got one with 11,000 miles on it (a 2005). This truck was used in the DC area as some type of CIA or EPA truck - it had a high-powered alternator system installed, a throttle regulator, and a 1000W 12V -> 120V inverter installed. I found out later it had about 2500 hours on the engine (equivalent to 60,000 miles), so it wasn't super low-use as I had thought.

Anyways, this was used on the East Coast where there is obviously rust. The truck is used here for work purposes, and I drive a 1998 BMW 5-Series around as my daily driver, so this truck doesn't get too many miles on it (just up and down to Mammoth 5-6 times a year). Well, the other day I took my trailer out to take my 914 to the painter (another long story). On the way back, the brakes started squeaking - you know the kind of squeak that happens when the little metal tab starts contacting the rotor indicating that you need to replace the pads in a short while. Or so I thought?

Well, the squeaking continued, but it wasn't that loud, and we didn't put more than a handful of miles on it since it started. Since we were leaving on our 83-day RV trip across the country (another long story), I figured I would just take care of it when I got back. Well, my wife flew back a few weeks before I got back, and she was driving the truck around in the meantime. The squeaking continued, but she was only putting a few miles a day on it.

So, last week, she mentioned that the pedal went to the floor and she lost a lot of braking power. She also sent me a photo that showed me what appeared to be brake fluid sprayed all over the inner wheel well. Well, that can't be good, so I told her to stop driving it and that I would look at it when I got back. I figured it was a cracked brake hose or something somewhat typical like that.

Well, that was tonight. When I looked under the car I really couldn't believe what I saw. I still have no idea what happened. A whole one-half of the brake rotor is completely missing! Not one-half like a half-moon, but one whole side (inner side) of the vented brake rotor. It's completely gone! It looks like the inner vents rusted through and then the inner brake rotor half was wobbling and/or cracked and then broke in two and fell off? The other side looks semi-normal (very well worn). The piston on the side with the missing half looks like it was rubbing against the internal fins of the inside of the rotor and it looks like it destroyed the piston / caliper. Funny thing is, it was *not* making a ton of noise - even tonight when I moved it out of my driveway.

Anyone seen anything like this before?
Here's the shot of the brake fluid sprayed in the rear wheel well:



Here's the shot of the missing half of the rotor. Blue arrow points to the outer half of the rotor. The Green arrow is just the thin dust shield:



The closest I could find was this video on YouTube, which is similar, but the rotor half is still there.



Thoughts?

-Wayne

[RNajarian]

I lived in Ohio for 15 years and saw some badly rusted cars but NOTHING as crazy as this. My only thought is I’m glad your wife wasn’t hurt.

Do the other rotors show any damage?

[manbridge 74]

Looks like it’s a pic from the “Just rolled into the shop” site....

Probably seized inner piston failing to retract fully. Common GM issue in areas of high salt use.

[Wayne 962]

No damage to the other rotors, but they seem rusty as well. Still, where did the other half disappear to?

-Wayne

[Wayne 962]

Ha. On "just rolled into the shop", I found a photo of something very similar. They are joking about it on the site, as the customer says "it just started making the noise, and it was a small squeak." I can attest that this did not make very much noise at all!

-Wayne

[Oneredspyder]

I have lived on the East coast for 40 years and can tell you that you have no idea of what and where that truck has been through. Many people drive there cars and especially trucks through salt water like it is nothing. Near the beaches they pick up salty sand. I had problems with GM brake discs years ago and found that I could by Discs from China at 1/4 of the American prices. Who do you think your corner shop is going to use.
A little rust, a little warp, a little force, and the devil pops it apart.
Last spring a friend's new leased car was flooded by the ocean. He brought it back to the dealer to check it out. They gave him a new car and he asked what they were going to do with the other. They told him they were going to clean it up and sell it. No carfax or insurance report. Just dipped in salt, 6 months old. What a deal.

[911tracker85]

I just saw something like this at the shop. a rotor laying on the floor with the little fins showing.

a few years ago I suddenly started hearing metallic scraping on the way back from a track event.

had just checked before the trip and had a lot of pad left.

when we pulled the caliper, found the brake pads on one side had separated from the backing and had fallen out. heaving scouring on the rotor. the pad on the other side was also separating from the metal backing plate but had not broken into pieces and fallen out.

when I was at the ford dealer not long after that, I took that in and asked what they knew about such an issue.

"we just fix 'em, we don't design them."

[jpnovak]

I see half brake pads and backing pads on the road all the time riding my bike. Makes me wonder why I still ride my bike...

Not sure how they can come out. I assume that the piston probably dropped out after the pad was no longer holding it in place.

If otherwise good, fix the caliper, lube the guide pins and put new pads in it.

[kennethg]

That happens all the time up in Truck country Alberta.

More often than not the outer pad is seized in the caliper bracket causing the inner to do all the work and increasing pad wear to the point it goes steel on steel. Rotor wears to the point that the inner pad is thin enough to fall out between the rotor and caliper bracket, once that happens the piston moves out of the caliper bore and here comes the brake fluid.

We see something along those lines a couple times a year. Some I've road tested some with no noise at all, you pull the wheels for an inspection and wonder how the hell you got around the block without killing anyone.

[jjeffries]

GM's rotors and drums in that period were of appalling quality; I haven't seen this exactly but did see other similar horrors with failed brake parts that were genuinely shocking. John/CT.

[175K911]

Good friend has the same vintage 2500 4wd big block truck, had rotted out fuel lines on what was supposed to be a "well maintained" suv.

Also, having lived in the DC area for 13 years, and knowing how some of the government vehicles are maintained- work goes to whoever was the lowest bidder for that year- who knows what brake rotors may have been on your truck. Likely some $13 cheapo.

But the most important thing is that your wife didn't get hurt, or hit anyone else either. Can you imagine if you'd been hauling the RV when your foot went to the floor?

[DanielDudley]

Originally Posted by 175K911

Good friend has the same vintage 2500 4wd big block truck, had rotted out fuel lines on what was supposed to be a "well maintained" suv.

But the most important thing is that your wife didn't get hurt, or hit anyone else either. Can you imagine if you'd been hauling the RV when your foot went to the floor?

Best check your fuel and brake lines, Wayne. They go out all the time on these rust belt GM trucks. If you have the later coated lines, you are OK. If not, you need to really check them out thoroughly.

[sugarwood]

This is why I like to replace rusty rotors.

Love that Wayne drives an E39 for his DD.

[djpateman]

Many years ago I took a caliper off of the rear of a 914 and one piston face was wearing on the rotor. The remains of the pad backing plate was badly warped but still in place with the piston poking through it.
A very long time ago a group was walking the track at Shannonville and I picked up a backing plate from a motorcycle pad around the back half of the track. We started joking about where the remains of the motorcycle might be found. Very serious business to lose such parts on the track.

[irl]

I think this is off topic for the forum, I think Im going to have to ask a moderator to move it.

[mepstein]

That's just getting broken in.

Typical here on the east coast.

Imagine what happens to old Porsches.

[Dpmulvan]

Our roads are heavily salted anywhere from October through March. Rotted frames, frozen rusted calipers, rotted fuel and brake lines and a host of other issues. With the salt belt GM trucks rotted rockers from inside out and bad grounds are the most common issues. A vehicle up here is totally trashed after 5 or 6 winters.

[billybek]

Was driving down Highway 1 @ Walteria a big heavy half moon chunk of iron went through the trunk of the SC, punctured the fuel tank and the car burst into flames.

No idea what it was or where it the object came from.....

Originally Posted by Wayne 962

No damage to the other rotors, but they seem rusty as well. Still, where did the other half disappear to?

-Wayne

Glad no one was hurt. I had to replace the rotors on my 04 GMC 2500 HD. Not because they were worn out but they were rusted too badly to cool properly. Those rotors with the internal parking brake assembly are not cheap!

Stainless are available $$$$ but where you are rusting should not be a problem from here on out.

[cabmandone]

Wow! You would think half of the rotor falling off would make some kind of racket other than a brake squeal! I swear this brine they put on the roads during the winter is a part store owners' dream come true.

[Porchdog]

I have seen that plenty here in PA. More often with Ford dual piston calipers but my sample size isn't all that large.

As others have said above, seizing of the calipers due to corrosion. I have seen a few with the piston against what's left of the rotor.

Also as noted above take a careful look at the fuel and brake lines. I like the copper-nickel brake lines myself.