boiled brake fluid and flat spot-ed tyres

SkurdalenFox · 04-03-2008, 04:32 PM

I went to a informal little autocross last weekend. Since there were only a few of people, I got to run the course over and over without stopping. After half a dozen laps my brake pedal starting getting shorter and shorter. There was a straight part in the course. I got up to ~ 70, then had to brake hard to make a couple tight turns. After half a dozen laps my brake pedal starting getting shorter and shorter. As I hit the braking zone again, my ABS failed, and I locked the tires. I stopped and my brake fluid was boiling, and the pads were smoking.

I'm not sure why the ABS failed. It started working again after the brakes cooled down.

Anyhow, here's the damage cause by the heat and the wheel lockup.

I flushed the brake fluid. I had put new fluid in the day before. The fluid was bright green. Weird.

Do the rotors look okay? There is no pulsating if I touch the brakes at speed.

Here's a tire. You cannot tell from the photo, but they're flat spot-ed. I trimmed the chunks off the leading edges of the tread blocks. I also moved the fronts to the rear. On the way home, with the fronts still on the front, there was much vibration. Now that the fronts are on the back, there is no vibration. Will the damaged tires re-round themselves? Or, am I looking at buying some new rubber?

Sendero · 04-03-2008, 04:58 PM

Buy new tires.

The ABS probably failed because the fluid inside the controller was boiling too. No pressure from the master cylinder equals no pressure when the ABS activates. If you're using store brand brake fluid you really need to think about changing. Ford makes a "High Performance" DOT3 fluid that I would HIGHLY recommend called Ford HP (link).

I know it was an improptu autocross, but give your car a little rest next time. Also, the course design should never allow street cars to reach 70mph nor have a huge straight followed by tight features at the end of it. Those usually spell disasters when someone doesn't check up or "put both feet in" after a screwup.

rtusnake · 04-03-2008, 05:13 PM

Maybe a burnout will help even the tires out

militarymustang88gt · 04-03-2008, 05:44 PM

yes a burnout is needed. well not to help the tires but to not make you seem like you wasted all that money on two tires. at least you got to see something cool from them.

banditmwp · 04-03-2008, 08:22 PM

Quote:

Originally Posted by militarymustang88gt

yes a burnout is needed. well not to help the tires but to not make you seem like you wasted all that money on two tires. at least you got to see something cool from them.

tayzoid1 · 04-03-2008, 09:09 PM

or you could give them to me

and i will run them becouse ive never had anything but used tires on my stang
i am broke as a joke so dd tires arent my first prioritie(nor is spelling) as long as they dont blow out or leak and their the same size we are good

ncontt · 04-07-2008, 03:44 PM

Quote:

Originally Posted by tayzoid1

or you could give them to me

and i will run them becouse ive never had anything but used tires on my stang
i am broke as a joke so dd tires arent my first prioritie(nor is spelling) as long as they dont blow out or leak and their the same size we are good

Sendero · 04-07-2008, 06:33 PM

Quote:

Originally Posted by ncontt

tayzoid1 · 04-07-2008, 10:47 PM

werd to yo motha bitches

ncontt · 04-10-2008, 05:10 AM

lmao....

04-03-2008, 04:32 PM	#1
SkurdalenFox Senior Member Join Date: Sep 2005 Location: Boulder, CO Posts: 463	boiled brake fluid and flat spot-ed tyres I went to a informal little autocross last weekend. Since there were only a few of people, I got to run the course over and over without stopping. After half a dozen laps my brake pedal starting getting shorter and shorter. There was a straight part in the course. I got up to ~ 70, then had to brake hard to make a couple tight turns. After half a dozen laps my brake pedal starting getting shorter and shorter. As I hit the braking zone again, my ABS failed, and I locked the tires. I stopped and my brake fluid was boiling, and the pads were smoking. I'm not sure why the ABS failed. It started working again after the brakes cooled down. Anyhow, here's the damage cause by the heat and the wheel lockup. I flushed the brake fluid. I had put new fluid in the day before. The fluid was bright green. Weird. Do the rotors look okay? There is no pulsating if I touch the brakes at speed. Here's a tire. You cannot tell from the photo, but they're flat spot-ed. I trimmed the chunks off the leading edges of the tread blocks. I also moved the fronts to the rear. On the way home, with the fronts still on the front, there was much vibration. Now that the fronts are on the back, there is no vibration. Will the damaged tires re-round themselves? Or, am I looking at buying some new rubber? __________________ Jim

04-03-2008, 04:58 PM	#2
Sendero Im gonna show her my... Join Date: Dec 2004 Location: Somewhere providing FREE tech support. Posts: 4,269	Buy new tires. The ABS probably failed because the fluid inside the controller was boiling too. No pressure from the master cylinder equals no pressure when the ABS activates. If you're using store brand brake fluid you really need to think about changing. Ford makes a "High Performance" DOT3 fluid that I would *HIGHLY* recommend called Ford HP (link). I know it was an improptu autocross, but give your car a little rest next time. Also, the course design should never allow street cars to reach 70mph nor have a huge straight followed by tight features at the end of it. Those usually spell disasters when someone doesn't check up or "put both feet in" after a screwup. __________________ I heard it on the internet, so it must be true. "I believe that a person's moral compass can be determined by how he references free men the right to defend themselves." T. Nugent "An armed society is a polite society. Manners are good when one may have to back up his acts with his life." R. Heinlein "Never argue with an idiot. They drag you down to their level, then beat you with experience." -Unknown

04-03-2008, 05:13 PM	#3
rtusnake Halfshaft Killer Join Date: Mar 2005 Location: The Kingdom Posts: 3,910	Maybe a burnout will help even the tires out __________________ 03 Cobra 06 F250 (\__/) (='.'=) (")_(")

04-03-2008, 05:44 PM	#4
militarymustang88gt Senior Member Join Date: Jun 2007 Location: bham and auburn Posts: 337	yes a burnout is needed. well not to help the tires but to not make you seem like you wasted all that money on two tires. at least you got to see something cool from them. __________________ finally got my avatar. it is the white one.

04-03-2008, 09:09 PM	#6
tayzoid1 5.slo stanger Join Date: Jan 2007 Location: oxford alabama Posts: 735	or you could give them to me and i will run them becouse ive never had anything but used tires on my stang i am broke as a joke so dd tires arent my first prioritie(nor is spelling) as long as they dont blow out or leak and their the same size we are good __________________ no mustangs anymore but i do have a 1jz swapped 83 supra Last edited by tayzoid1; 04-03-2008 at 09:12 PM.

04-07-2008, 10:47 PM	#9
tayzoid1 5.slo stanger Join Date: Jan 2007 Location: oxford alabama Posts: 735	werd to yo motha bitches __________________ no mustangs anymore but i do have a 1jz swapped 83 supra

04-10-2008, 05:10 AM	#10
ncontt pro-jackstand racer Join Date: May 2005 Location: Milner, Ga Posts: 2,473	lmao.... __________________ And God created Neil Peart so that lightning would make sense to the world. ~~~~~~~~~~~~~~~~~~~~~~~~~~~