BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > BIMMERPOST Universal Forums > General Automotive (non-BMW) Talk + Photos/Videos
 
Post Reply
 
Thread Tools Search this Thread
      04-26-2011, 12:03 AM   #1
-=Hot|Ice=-
Been There, Done That.
 
-=Hot|Ice=-'s Avatar
 
Drives: 2013 BMW M3
Join Date: Jan 2008
Location: Maryland

Posts: 4,727
iTrader: (0)

MotorTrend:Why the Boss Mustang Failed Our Brake Test

Quote:
Originally Posted by MotorTrend
Road test editor Scott Mortara headed down the quarter mile in the bright-yellow Boss 302 Mustang, steadying his speed for Motor Trend’s standard brake test, just as he’s done a thousand times before. Back in the day, before anti-lock brakes and stability control systems and decent tires, you never knew quite which direction the car might be facing when you finished a brake test. These days, though, it’s fairly simple: At about 70 mph, you grenade the brake pedal and hang on. The electronic nannies keep the cars nice and straight, and our sophisticated on-board data-logging equipment automatically captures the distance it takes to decelerate from 60 mph to a standstill.
So when Scott punched the Mustang’s brake pedal and it went straight to the floor, it got his attention. He quickly ran the six-speed manual back through the gears, slowing the car enough to make it through the gap in the wall at the end of the track.
Total brake failure during regular performance testing is a very rare occurrence. I’ve had plenty of cars get squishy pedals and smelly pads after hot laps around a road course. But in more than 25 years of testing, I’ve never known of such a complete—and potentially catastrophic—loss of braking.
Earlier, this particular Boss 302 had repeatedly lapped Laguna Seca and been driven enthusiastically along some of California’s more challenging back roads. Scott had then driven it directly back to Motor Trend HQ in El Segundo so we could get the photos, video, and test numbers we needed for last month’s print and iPad editions, as well as our website and YouTube channel. Had the Mustang’s brake pedal gone to the floor any time in the week before it did, the consequences could have been horrifying.
So what went wrong? Scott heard a metallic snap as he braked. A quick look in the Mustang’s footwell revealed the pin connecting the pedal to the master cylinder clevis rod end had sheared.
The Mustang’s brake pedal arm is normally located between the two sides of the clevis, and even if the clevis pin should fail, after a very short interval the back side of the pedal arm would act against the base of the clevis with enough force to actuate the master cylinder and apply the brakes. But for some reason, the pedal arm in this car had been pinned to the outside of the clevis, on the right-hand side. This concentrated all the force acting on the clevis pin on a single point, causing it to shear; and when the pin failed, the pedal slid past the rod that actuated the master cylinder. The result? No brakes.
Ford reacted instantly to news of the failure. Our Boss 302 was collected and sent away for a tear-down and inspection. The Mustang line was shut down, and every brake assembly checked. Ford also reviewed its process to ensure incorrect attachment of the brake pedal arm to the master cylinder clevis rod end could not occur. We’re told no anomalies were found. And we haven’t seen anything awry on the Mustangs we’ve checked since.
How the arm was misassembled on our Boss 302 tester remains a mystery to Ford, and to us. The only thing we can think of is this particular car’s master cylinder had been removed after it left the factory, and the incorrect connection to the brake pedal arm made when it was reinstalled, although we have no proof either way. Based on the evidence, we’re prepared to chalk this incident up to a freakish combination of circumstances.
Modern cars are amazingly robust and reliable. However, stuff can—and occasionally does—go wrong. That’s why we test.

Read more: http://blogs.motortrend.com/boss-mus...#ixzz1KbPq4reN


http://blogs.motortrend.com/boss-mus...est-14593.html
__________________
Quote:
Originally Posted by Jaypod View Post
You sound like my buddies who have AMG's - Slam the gas, slam the brakes...
-=Hot|Ice=- is offline   United_States
0
Reply With Quote
      04-26-2011, 12:33 AM   #2
Year's_End
RWD only.
 
Year's_End's Avatar
 
Drives: '08 E92 335i
Join Date: Feb 2007
Location: St. Pete, FL

Posts: 12,293
iTrader: (0)

Yeah, saw this article. They say the best reasoning for the failure would be a botched re-installation by some goon after fiddling with the car past its assembly finish point. That seems like the only plausible idea imo, considering this never happens in road tests.

Quote:
Ford reacted instantly to news of the failure. Our Boss 302 was collected and sent away for a tear-down and inspection. The Mustang line was shut down, and every brake assembly checked. Ford also reviewed its process to ensure incorrect attachment of the brake pedal arm to the master cylinder clevis rod end could not occur. We’re told no anomalies were found. And we haven’t seen anything awry on the Mustangs we’ve checked since.
How the arm was misassembled on our Boss 302 tester remains a mystery to Ford, and to us. The only thing we can think of is this particular car’s master cylinder had been removed after it left the factory, and the incorrect connection to the brake pedal arm made when it was reinstalled, although we have no proof either way. Based on the evidence, we’re prepared to chalk this incident up to a freakish combination of circumstances.
__________________
E92 335i: Space Grey|Coral Red|Aluminum Trim

Future Ride: 2015 Mustang GT Premium |Guard|401A|PP|Recaros|6MT
Year's_End is offline   United_States
0
Reply With Quote
      04-26-2011, 12:33 AM   #3
Sylon
Brigadier General
 
Sylon's Avatar
 
Drives: 2011 135i, SG/CR, 6MT, M-Sport
Join Date: Apr 2010
Location: Michigan / Ohio

Posts: 3,411
iTrader: (0)

Garage List
2011 135i  [4.60]
Sounds like a freak accident. And it seems like Ford jumped all over that like Lindsay Lohan on a necklace. Its just a good thing nobody was hurt and it appears to be an isolated incident.

One thing is for sure, somebody somewhere is getting fired.
__________________

2011 BMW 135i | Space Gray | ///M-Sport | BMW CCA #450291
Facebook / Instagram / YouTube / Twitter
Sylon is offline   United_States
0
Reply With Quote
      04-26-2011, 12:36 AM   #4
Year's_End
RWD only.
 
Year's_End's Avatar
 
Drives: '08 E92 335i
Join Date: Feb 2007
Location: St. Pete, FL

Posts: 12,293
iTrader: (0)

I just hope people don't start using this as some sort of reason to start bitching about Mustang reliability.
__________________
E92 335i: Space Grey|Coral Red|Aluminum Trim

Future Ride: 2015 Mustang GT Premium |Guard|401A|PP|Recaros|6MT
Year's_End is offline   United_States
0
Reply With Quote
      04-26-2011, 09:01 AM   #5
OBI_agent
D to the X to the B!
 
OBI_agent's Avatar
 
Drives: ABS,American bargain supercar
Join Date: Jul 2007
Location: Dubai

Posts: 2,096
iTrader: (0)

^^^+1000.

Like the GTR's failed trannies. Apparently, every GTR owner has that problem.

Anyway, I'm glad no one was hurt. After Insideline, I really like reading articles from Motortrend and it would have been a huge loss if something tragic happened. .
__________________
11 corvette C6

Last edited by OBI_agent; 04-26-2011 at 09:08 AM.
OBI_agent is offline   United Arab Emirates
0
Reply With Quote
      04-26-2011, 09:58 PM   #6
blue2fire
Brigadier General
 
blue2fire's Avatar
 
Drives: BMW 135i
Join Date: Jan 2009
Location: Location, Location, Location

Posts: 4,289
iTrader: (8)

It failed because they fiddled with it after production, must be embarrassing for Ford or not, based on their august reputation for quality products. Looking for Next Mustang thread in 5..4...3..2...
__________________

BMW CCA
Member #420568
Quote:
Originally Posted by Gordon Murray View Post
Being a fan of Honda engines, I requested that they consider building for the F1 a 4.5 liter V10 or V12. I asked, I tried to persuade them, but in the end could not convince them to do it, and the McLaren F1 ended up with a BMW engine.
blue2fire is offline   Cayman Islands
0
Reply With Quote
      04-26-2011, 10:06 PM   #7
ragingclue
One cam is enough
 
ragingclue's Avatar
 
Drives: VF
Join Date: Oct 2008
Location: mulletville

Posts: 6,774
iTrader: (1)

Talk about an "oh shit" moment....
ragingclue is offline  
0
Reply With Quote
      04-27-2011, 01:12 PM   #8
Sniz
Lieutenant General
 
Sniz's Avatar
 
Drives: e92 335 - gone // e36 M3 turbo
Join Date: Mar 2007
Location: Ellicott City, MD

Posts: 10,569
iTrader: (1)

Quote:
Originally Posted by ragingclue View Post
Talk about an "oh shit" moment....
not joking!

I had something similar happen. Had a 4,000lb trailer hooked up to my truck with a large hot tub on top of it, so probably close to 5,000lbs hooked up. Stopped at a stop sign in the middle of a long uphill grade. Sitting at the stopsign all of a sudden the brake pedal went to the floor, truck started going backwards quick. Luckily no one behind me. I hit the gas hard, transmission was pissed about having to stop the backwards movement with that much weight but it didnt fail. Was able to gas it to the top knowing I had no brakes. Luckily found a flat area at the top and slowed to a crawl w the parking brake which was on its way out too.....barely was able to stop the truck from 10mph w the parking brake. Stopping it on that hill would have been futile.

Then took about 10 deep breathes and called a tow truck. Metal brake line blew.

that sucked.


=============


back to the story, glad Ford jumped on the issue, hopefully it never happens again.
__________________
Sniz is offline  
0
Reply With Quote
      04-27-2011, 07:01 PM   #9
pmeloche
Lieutenant Colonel
 
pmeloche's Avatar
 
Drives: 2013 F25 X3 xDrive35i
Join Date: Feb 2008
Location: Montréal, Canada

Posts: 1,614
iTrader: (0)

Quote:
Originally Posted by Sylon View Post
like Lindsay Lohan on a necklace.
__________________

Patrice
2013 F25 X3 xDrive35i Vermillion Red
pmeloche is offline   Canada
0
Reply With Quote
      04-27-2011, 09:08 PM   #10
Impervious
UNC FTW
 
Impervious's Avatar
 
Drives: Black Sapphire 135i
Join Date: Dec 2010
Location: NC

Posts: 702
iTrader: (0)

Glad everything is okay, I'm sure this scare gave Ford a heart attack. Despite the brake failure it doesn't make me question Ford one bit. I know they want to take care of this especially with the bad press Toyota received.
Impervious is offline   Pakistan
0
Reply With Quote
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 08:05 PM.




m3post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST