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Do you want ABS

Maintenance/Repairs
#58

No no no no no.

Unless he had AIR BRAKES on a pickup truck, there is nothing between the brake pedal and the brake caliper pistons and wheel cylinders except brake lines, and brake fluid.

The way an ABS system is routed is that the brake pedal pushes a rod into the back of the master cylinder.
The rubber seals in the master cylinder displaces brake fluid, and pushes it into the brake lines.
The brake lines then run through a combination box that balances the pressure for the front to rear bias, and at the same time is the box that has the actuators for the ABS function.
From there, the lines run to each wheel, feeding either a brake caliper (disc) or a wheel cylinder (drums).

Now, the way ABS functions is that the actuators in the ABS box are in a closed state.
Depending on the system, there is either one actuator per wheel, or a pair for the front, and a pair for the rear.

Under normal circumstances, when ABS function is not needed, the actuators are closed.
All the pressure goes directly to the calipers or wheel cylinders.

When the ABS computer senses that one tire is slowing down faster than the rest of the tires, then it opens that one valve long enough to make that tire slow down at the same rate as all the other tires. When the tire is slowed down enough, it closes the actuator, and brake fluid stops bleeding off.

Most ABS systems do not actuate when the vehicle is rolling backwards.
Your friend should have had full braking power.

Most ABS systems don’t actuate under a certain speed.
Your friend should have had full braking power.

Now, I don’t understand several things.

If it was a manual transmission truck, and was parked, one of two things had to have been in play if the truck was on a hill:

It was shut off with the truck in gear, and no parking brake.
It was shut off in neutral, with the parking brake.

Since it was on a hill, it has to have been in one of those two states.
If it was in neutral, without the parking brake, it would have rolled away.

Now, if it was in gear, without the parking brake, as soon as your friend hit the clutch to go and start the truck, it would have started to roll. In this case, backwards, as that is where the heavier load was.

Now, depending on the brake system for the trailer, hitting the brakes would have either done nothing with a combo that was going backwards (surge brakes), or should have done something (electronic).

Surge brakes work when the towing vehicle applies the brakes.
The trailer pushes forward against the TV.
There is a rod in the trailer tongue that pushes into the brake MC for the trailer, and activates the brakes.
If the trailer was going backwards with this type of braking system, then there was nothing your friend could have done to activate the trailers brakes. Chances are his truck left brake marks the whole way back from the truck’s system not being powerful enough to hold the trailer on a hill.

If it was an electronic brake system, the system relies on an electronic signal to turn on the trailer brakes. If the truck was still off, and was rolling backwards, there might not have been that electronic signal, so no trailer brakes.

I’m calling user error for the accident, not ABS failure.

BC.

#59

Craig, is that you in the next lane over? I’m waving at you. :stuck_out_tongue:

#60

The early systems read the pressure in the hydraulic system and the computer controls determined the amount of pressure being applied from his foot on the brake pedal according to the computer should have locked the wheels. It failed to take into account he had 14000 pounds of cattle and trailer on the back of the truck.

That is not how an ABS system, any ABS system, works.

I won’t repeat it all, but I’ll just say Bladecutter covered pretty much everything I was thinking.

And you are really telling me you never, not once, got in a truck that was in gear, stepped on the clutch and started it? You always put it in neutral first? Very odd.

#61

I agree…ABS on a bike is truely reserved for we “weeners”. I became one when I went from a Norton to a Honda.

#62

I’m not going to tell anyone else what to ride, but I know what I like; and I do understand that a “safe motorcycle” is an oxymoron.

#63

Seatbelts? I dont think that would be a great idea? What happens if it goes on its side and doesnt release itself? Even if designed to release, I wouldnt feel comfortable with a seatbelt on my bike.

#64

Its appalling to realize that so many of the people who have posted on here have absolutely no concept of what the safety device that you hate so much is actually supposed to do.

First off, the purpose of an airbag is to prevent you from hitting a hard surface.
Most typically, if you are in the drivers seat, this would be the steering wheel.
If you are in the passenger’s seat, this would be the dashboard, or the windshield.

Air bags work best in perfectly head on accidents, and if you are wearing your seatbelt.
Air bags still have to work if it is an offset accident, or if you are not wearing your seatbelt.
Their effectiveness is greatly reduced, however.

Think about it this way.
You are not wearing your seat belt.
Driving down the highway at 75mph.
A car traveling the opposite direction veers directly in front of you, and hits you head on at 75mph, also.

Without an airbag, and with no seatbelt, no matter what car you are in, you are most likely very dead.
Your chest hits the steering wheel, your head hits the windshield, the car crushes around your legs, and you die very quickly.

With an airbag and a seatbelt, you keep from hitting the steering wheel and the windshield, your legs are kept out of the crumple zone directly in front of your feet, and you have a raging headache and backache for a couple of days.

Now, for ABS.
For whatever reason, people think ABS makes your car stop faster.
No, that’s not it’s purpose.

The purpose of ABS if to prevent the tires from locking up, so that you can steer AROUND whatever object it is that caused you to slam on the brakes in the first place. Once your tires are locked up, you can not steer around an object in the road.

If you are in a curve, if you slam on the brakes, your car stops going around the corner, and heads in a straight line. If you are going around a right hand curve, that means you are skidding into oncoming traffic.

With ABS, when you slam on the brakes in that same corner, you will continue going around the curve, and not just slide into oncoming traffic.

Personally, if I am the one traveling in the opposite direction, I would MUCH rather you have ABS in your car, so I don’t have to test out the air bag and seat belt in my car.

I am that person who will always vote for more safety feature in cars, so I can be protected from the stupidity of others, which I have 0 control over.

BC.

#65

No seat belt? stypidity ! learning to operate the motor vehicle fully, comprehensive training, would also mean that the person has greater knowledge of what they want on their car with the logical thinking process to CHOOSE. …the subject matter of the OP. These features should be a selectable OPTION on vehicles. And you can bet that many logical thinking people will choose to have them. many won’t.

#66

Just to be clear, I do understand exactly what these “safety devices” are intended to do; and I don’t hate them, as long as they are installed in your car instead of mine. Fortunately for me, you don’t get to decide on what useless features are installed in my car (sorry, but big brother can’t protect you from everything).

#67

Some ABS systems have kept cars from stopping in time.

A poor reason not to have it. Usually it’s better to keep the wheels from locking up, thus preserving the ability to steer. Granted, wheel lockup may stop you (straight line) a bit shorter than with ABS, but more often it’s better to be able to steer out of trouble. ABS is safety equipment that is a plus most (but not all) of the time. Just as seat belts or air bags can kill you once in a while – should we get rid of them on the off chance that they’ll do that?

#68

This was a very early version of ABS. The truck was a late 80’s early 90’s model. Yes, I know the difference between electric trailer brakes and surge brakes and how they work. I also know what happened in this case.

I’m sure when he parked the truck he put it in gear and set the parking brake otherwise it would have rolled off while they were loading cattle. As is, it rolled off with him in it. He got in it and like any normal person put his foot on the brake, pulled it out of gear, started the engine and that’s when it started rolling. Dodge investigated the wreck, and we know what happened.

As far as starting one in gear, if you’ve ever fooled around with cattle, jumped in the truck with mud and cow shit on your boots you’ll learn not to do that the first time your foot slips off the clutch pedal and you break a motor mount.

Put simply, if not for the ABS actuating the truck should have sat there with the wheels locked exactly like it did for ever how long it took to round up the cattle and load them in the truck.

Some of these ABS systems in trucks are simpler than others, the simpler the better. Chevrolet’s system is the worst I’ve seen and their trucks have the worst brakes I’ve seen in a truck. Dad’s got a Suburban that takes a country mile to stop with a boat behind it thanks to the ABS. Ford’s system through 96 was fairly simple and much better that Chevy’s. The only experience I have with Dodge is the one I have now, and it’s not that bad but it’s a 3/4 ton, I don’t know if their half tons are any different. I know that the Germans worked on the Dodge suspension and I assume it’s brakes.

Skipper

#69

The original question regarding good tires vs ABS brings me to add this, I would prefer a well maintained vehicle with high quality tires, brakes, etc without the bells and whistles such as ABS. And I feel that an experienced and responsible driver in a well maintained vehicle likely has a better safety record than drivers who wish to push the envelope of safety, depending on technology to save them. And my experience with ABS, going back to the system mandated on trucks over 40 years ago, indicates that the improvement in safety is marginal, at best. And usually only beneficial in circumstances that a responsible driver would have avoided.

#70

I’ll confess that I probably could have used ABS to avoid an accident at least once in my life. Back when I was younger, less skilled, and at times reckless, I was unable to stop in time to avoid a collision on a rain-slick LA freeway. (For the record I wasn’t speeding, and the car had stopped unexpectedly in my lane with no lights on!) I jammed on the brakes and skidded into the car, mangling the front end of my Honda and causing thousands of dollars in damages. I’ve asked myself many times in the years since what would have happened had I pumped the brakes. And I also had some near missed when I was younger. I suppose better tires might have helped, but there was nothing below par about my tires. So while experience and good tires may help avoid accidents, I’m sure that there are millions of drivers today avoiding accidents because of ABS and they don’t even know about it. As for air-bags – the car I was driving that night didn’t have air bags, and had it the repair expense would have been that much more. I was glad not to have them that night and in other instances. When the car got older the cost of replacing the air bags could have made the difference between the car being repaired or totaled.

#71

Don’t know enough about cars to really have a concrete opinion on this. BUT I do know that in the last 3 months I have spent almost $1100 caused by ABS problems: first, had a wheel bearing/hub replaced in the left front (mechanism had shorted out). then, started having the same problem again and after deeper investigating this time around, had to have the entire harness replaced. NOT fun, esp. for a 24-year-old barely scraping by, saving up for a trip to italy in 10 days, and trying to get rid of the said car as soon as I take delivery on a smartcar (gee…wonder why I am trying to get rid of it).

so, basically, NOT happy with ABS right now

#72

I have spent almost $1100 caused by ABS problems: first, had a wheel bearing/hub

What does a wheel bearing have to do with ABS??

#73

well, the whole hub unit shorted out (due to faulty wiring, as we finally figured out the second time this happened), so that the wheels were communicating to the ABS system that the car was slipping everytime I would hit exactly 3mph. so, when i would apply the breaks under normal conditions, the second the car hit 3mph, the ABS would engage and my car would slip, as if i had just slammed my foot down on the brake in the middle of a rainstorm.

#74

For those who enjoy the economy of maintaining vehicles for many years of safe and reliable service, technologies such as ABS, traction control, SRS, etc., loom as formidable obstacles which add to the growing list of causes for vehicles to be more disposable year to year. An ABS module may cost more to replace than an otherwise serviceable car is worth.

#75

Your saying it’s a problem caused by ABS…It’s actually a wheel bearing problem. ABS has NOTHING to do with the problem…just the symptom.

#76

For those who enjoy the economy of maintaining vehicles for many years of safe and reliable service, technologies such as ABS, traction control, SRS, etc., loom as formidable obstacles which add to the growing list of causes for vehicles to be more disposable year to year.

Maybe!!! But you can say that about almost every part on your car. Power Steering, Power Boost Brakes, Turn signals, Power Windows, Power Seats, Rear Window Defogger, AC, Fuel Injection, Multi Link Suspension…etc…etc

#77

Is there some rhetorical issue here? The ABS sensor was integral to the hub/bearing. Not only that but most vehicles today have pre-assembled hubs with or without ABS and cost in the hundreds of dollars. Previous hubs were serviceable and the individual bearings usually cost less than $12 per wheel and a first year high school vo-tech student could replace them with common hand tools in less than an hour. And also, bearing rarely failed, often lasting hundreds of thousands of miles while todays costlier hubs fail often. I have replaced many more hubs in the past few years than serviceable bearings in the many decades prior. I can likely operate any of my 'primitive’vehicles as safely and more economically than any new top of the line automobile.