# Catastrophic brake failure



## archfubar (Nov 3, 2011)

Hi all,

This is my first post on this forum, and unfortunately it's quite a story. I don't expect anyone to have the answer to my problem based on what they read here, but I'd like to bounce it off of you all to get some ideas that come to your minds.

I'll start by introducing my vehicle: It's a 1997 king cab XE 4wd. I bought it used about 2 years ago and it has around 104k miles.

So, I was driving down a divided highway a couple of days ago. I had just cut up some fallen tree limbs and had some wood in the back of my truck. I didn't have a huge amount of wood in the back, but I had some (maybe a couple hundred pounds).

I was distracted by my GPS (I know, lesson learned, I won't do it again) and when I looked up there was a line of stopped traffic in front of me. I hit the brakes hard and fish-tailed a little bit. My choice was either to rear-end the vehicle in front of me or go up on the curb to my right. I chose the curb. I hit it pretty hard and came back down and managed to stop without any further incident. I didn't know if I had damage, so I pulled off into a nearby parking lot and parked. I looked at my passenger's side front tire and it was flat as a pancake. The rim was also messed up, which isn't surprising. 

What worried me the most was that when I pressed the brake it was like a sponge and went all the way to the floor. I looked underneath the truck and there was brake fluid all spilled out. I got towed home. I had to turn on the truck to move it a little bit for the tow truck and I noticed the ABS light was on. I assumed, at the time, that this was because the system was dry, not necessarily because there was an ABS problem specifically.

What I'm trying to figure out is what might have happened. I can't decide if the brakes gave out before or after I hit the curb. I can't see where the fluid was leaking from, but it definitely wasn't from a brake line connected to a wheel, it was leaking from somewhere more toward the middle front of the truck and higher up (like maybe above the transmission). 

I got to thinking that I'm pretty sure that's the first time I ever hit the brakes hard enough on the truck to engage the ABS. Is it possible that there's some flaw with the ABS hydraulics that may have caused a rupture when it tried to engage? I don't know enough about the system to know if that's an intelligent guess, or what components are out of my sight in the area of the truck I described to you.

Any theories or diagnostic suggestions are certainly welcome. Has anyone ever heard of anything like this? If you need more information, let me know and I'll be happy to share.


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## Scott_T (May 15, 2011)

Probably rust. I had to replace all the lines on mine from the cab back this summer.


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## SPEEDO (Jun 9, 2003)

had to break a line.. (the abs actuator is mounted on the rear diff) pop the hood and trace the lines to the caliper...


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## archfubar (Nov 3, 2011)

Thanks for the tips, guys. 

So I had someone pour some brake fluid into the master cylinder and then press the brake pedal while I watched underneath the truck. Sure enough, one of the steel lines had rusted out and ruptured. I guess I should have been diligent about checking them before one of them burst when I really needed it. Oh well, at least I didn't run into anyone or do any serious damage to the truck.

Apparently Nissan doesn't make the line I need anymore, so I'll have to bend a new one and flare it myself. Is this something that's feasible to do for a novice to do? (obviously I'll need a decent flaring tool and some bending pliers). Does anyone have any tips that might make the task more straightforward?

I appreciate any insights you can provide.


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## SPEEDO (Jun 9, 2003)

I thought NAPA would bend lines....


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## jdchandler13 (Dec 9, 2011)

some of them will and some of them wont, its kinda like o'reilly's, some stores can make hydraulic hoses for you and other stores dont have the stuff there to do it.


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## jdg (Aug 27, 2009)

Brake lines are one of those things I wouldn't mess with.....until I had a pro show me the right way to do it and the right way to get that "double-flare" thing done right.
Too many things to go wrong, too many ways to mess up the flare so it fails at exactly the wrong time, etc.
That's my advice... Sure you can do it and the correct tools aren't too expensive. It's a bit tricky if you've never done one before. Not rocket science, but if you're gonna do it yourself, try and find somebody that knows how to do it right.


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## archfubar (Nov 3, 2011)

That's a good point, Jdg. I didn't want to do it myself if I had to make my own double flare, as I'd never done it before. It turned out that the line that went was a typical 3/16" wide by 51" long line. You can go down to an auto parts store (I went to autozone) and get a 51" length of 3/16" brake line with the flares already done. All you have to do is bend it and screw the ends in to the appropriate places. It turned out to be a blessing in disguise that nissan doesn't make the pre-bent line I was looking for anymore, because I got the pre-flared section for about $7 (rather than the $80 or so for the pre-bent), borrowed a tubing bender from my wife's uncle and now I can replace other lines as necessary, providing I can find a standard, pre-flared length that's close to the same size as the original.


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## dvdswanson (Nov 6, 2005)

on a side note, since you hit the curb and destroyed your wheel/tire, I would look at your steering, idler arm in particular, this is a weak point in an IFS set up and its probably bent.


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## jdchandler13 (Dec 9, 2011)

Hey guys I'm gonna run this one by everybody, as I am having a bit of a failure myself... I did a tune-up on my 87 2.4 2wd (plugs,wires,cap,rotor,and front brakes (pads,rotors) and it has turned into an absolute cluster if u catch my drift. Now not only do I not have brakes, the truck won't idle and when u press the brake pedal, it will shut the truck off. I am @my wits end as to how to fix it. I made sure the wires are connected properly, the cap and rotor are both correctly installed and I have replaced every vacuum line I can find w new rubber to rule out the leaks and I'm still having the same problem. The truck was smooth idling before and I had a brake pedal even tho the pads and rotors were shot. When u crank it it lopes like a monster small block. It is overfueling but not to the point of smoking. One thing I did notice is that the truck had the same plugs on both sides but it calls for 2 different heat intake vs. exhaust but that's the only thing I changed from why was on it. I even changed the brake booster to make sure it wasn't leaking and its actually gotten worse. This is my dd so any help would be so greatly appreciated


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## jdg (Aug 27, 2009)

Get in there with a can of carb cleaner and start spraying it around waiting for the engine to smooth out....taking care to try to not spray it down the intake. Whether you replaced the vacuum lines or not, I'd bet you knocked one off and/or didn't put it back in the right spot (i.e. EGR valve...if so equipped). The fact that you step on the brakes and kill the engine also suggests massive vacuum leak in that new booster. Block it off and give it a shot.


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## jdchandler13 (Dec 9, 2011)

Thanks for the help guys. Determined it was the booster, half tempted to put the old booster back in so I have a brake pedal and just block off the vacuum to the booster bcuz when I blocked the vacuum off the idle smoothed out and it acted like a different animal. Also I was wondering if changing the heat range of the plugs could b causing it to bog down in the upper rpm range.


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## smj999smj (Jan 1, 2006)

Normally NGK BPR6ES plugs are put on the intake side and BPR5ES plugs are put on the exhaust side. The "5's" are a "hotter" plug than the "6's." Some will use the option plug, the BPR5ES on the intake side and that's usually fine.


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## jdchandler13 (Dec 9, 2011)

Thanks so much for the help everybody. I was wondering if it would hurt anything for me to run the truck w the booster blocked off and just run manual brakes? I know it will run w/o power brakes I just didn't know if it would damage the master cylinder because its designed for the hydro assist. Also does anyone think the cooler plug on the intake side could be causing the stutter at higher rpm? Like I said in the previous post the idle is silky smooth but when I took it out for a road test it drives fine until the upper rpm range and then it bogs horribly. The previous owner had the bpr5es plugs on both sides. Thanks again for all the help everyone.


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## smj999smj (Jan 1, 2006)

The BPR6ES's shouldn't be a problem on the intake side. That's what the engine should have in it. Running with the booster disconnected won't hurt the master cylinder at all, but it's not the same as "manual brakes," technically; unassisted power brakes are less affective than manual brakes. If your using it as a "farm use" vehicle, it's not an issue, but if you're going to be driving on the road with other vehicles or off-road where you'll really need those brakes, you would be best off to repair the brakes properly.


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## Grug (Aug 20, 2009)

Hey archfubar, how'd you make out with the brakes? Did you get one installed?

How'd the bleeding go? If things are kinda' rusty you might wanna' soak the bleeder nipples with PB Blaster (or another good penetrating oil) well in advance of when you actually attempt to turn the nipple to bleed the wheel.


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