Last week we traveled from Canberra through Cooma to Bemboka (close to Bega). This involved driving down Brown's Mountain, one of the steepest and windiest pieces of road we've traveled on. This was made worse by road crews repairing a slip closing off one lane with automated traffic lights. The brakes failed when we tried to stop at these lights and we had to proceed through the red light on the wrong side of the road hoping that nothing was coming the other way - fortunately it wasn't.
The cause of the brake failure was overheating and we got the truck checked over as soon as we could. Testing showed that the brake fluid was probably the original brake fluid installed during manufacture and it was in such poor condition that the truck should not have been on the road. This was despite the damn thing being serviced by the manufacturer's agents every 10 000 km as detailed in the handbook which also indicated that the brake fluid should have been replaced at 40 000 km (its done 55 000 km).
The post is not so much to complain about the incompetence of the servicing agents but to get people to get their brake fluid tested and if necessary replaced so something similar doesn't happen to them. I didn't know such tests existed or the consequences of having brake fluid in such poor condition but I do now. It only takes a couple of minutes and could save you your life.
Regards
Dave
blaze said
05:55 PM Feb 15, 2016
I have also experienced brake fade to the point of failure, the reason was going down a steep hill too fast in to higher gear. Never blamed the brake fluid. Now I am not saying you were going too fast and not selected the right gear but I haven't yet seen brake fluid fail to that extent. The reason brake fluid fails is it attracts moister and under excessive braking that will boil off causing the fade.
cheers
blaze
Peter_n_Margaret said
06:24 PM Feb 15, 2016
When you see a sign that says "Trucks and Busses Must use Low Gear" that means the gear selected must retard the vehicle sufficiently that no brakes are needed at all.
So if the brakes are used by those vehicles, an offense has been committed.
That would seem to be a good guide for ALL vehicles, not just trucks and busses.
It would seem to me that a light weight vehicle with 3T of van is a disaster waiting to happen.
The cause of Dave's brake failure was overheating, as he said. Nothing to do with brake fluid.
Cheers,
Peter
erad said
06:48 PM Feb 15, 2016
Brake fluid is hygroscopic ie it absorbs water. This lowers the boiling point of the fluid dramatically and can cause what happened to you. Two things are wrong in your case.
1 Obviously the brake fluid boiled. This was most probably due to absorbing water - see above. It could also be that the service department actually did replace the fluid and that the stuff they used was already slightly contaminated. (I suspect that the fluid was not changed).
2 You probably drove down Brown Mountain without using your gears, or at least not using a gear low enough to hold the load without overloading yoiur brakes. I regularly go up and down the mountain and I barely touch the brakes. OK - I am as slow as a wet week, and at times traffic builds up behind me but as soon as possible I pull over and let them pass. I often smell Fried Ferodo from other cars when I get near the bottom of the hill.Two weeks ago, I went down the mountain with my caravan and I used the brakes only on the hairpin bends. I was taught years ago that if you need 3rd gear to go up a hill, you need 2nd gear to go down it.
Regarding point 1 above, years ago my wife's car was going out of warranty and I took it to the dealer for the last time because I service my vehicles myself. Part of the service was to replace the brake fluid (oddly enough not the clutch). When I got it home, I jacked up the car and checked. Sure enough, the bleed nipples still had road grime on them and not a sign of brake fluid. Straight back to the dealer and asked "Did you replace the brake fluid?" 'Yes Sir' was the reply. Some unprintable response from me evoked action and the fluid was replaced whilst I watched it being done. Your experience was precisely the reason I checked it (plus my mistrust of dealer service anyway). Further, water in the brake fluid can cause corrosion of wheel and master cylinder components. leading to ultimate brake failure. Not good. Manufacturers specify change intervals fro a very good reason.
These days, your local mechanic probably has a fluid conductivity meter which measures the percentage contamination of water in the brake fluid. Maybe you should get someone to check it and if it is high, go straight back to the dealer and (politely) tell them what you think...
Some years ago, I did a driver training course with the Aust Federal Police in Canberra. Fantastic 2 days. One of the questions I asked was "Modern Falcons, Commodores and Magnas all have 4 wheel disc brakes, so braking on modern cars should be no problem" As usual, I was wrong. The instructors said that brakes on modern cars were OK for 1 stop from 100 km/h. They taught us Threshold braking, where you hit the brakes fairly hard and let the car's nose dive. This loads up the front wheels and once the nose has dipped, then you really stand hard on the pedal and wait for a wheel to lock up. As soon as it does, you ease off the pedal slightly until the wheel starts turning again and then load up the pedal again. The stopping distances possible are amazing. Then, they got us into a standard VP Commodore and we started practising threshold braking. After one stop from 80 km/h, it was back up to speed and repeat the process over again. The second stop had the pedal a bit spongy and the third stop the pedal was on the floor. OK - anyone who drives like that deserves to crash into something, but anyone who drives hard down Brown Mountain relying on their brakes is doing similar stuff.
I am not criticising you for running out of brakes - you were probably not aware of the limitations of your vehicle and the road conditions ahead - but it serves as a warning for others to watch out in similar conditions. Well done for alerting everyone to the problem.
Explorer said
06:51 PM Feb 15, 2016
In the "good old days" we were taught to go down a hill in the same or one lower gear than that we would need to come up it in. As Peter said if trucks & busses need low gear so does a car towing a caravan.
Something called gravity.
Mike.
KevKim37 said
06:57 PM Feb 15, 2016
Overheating of Brake Disc Pads can be a cause of Brake Failure as also can Overheating Of Brake Fluid that has Absorbed too Much Moisture as it is Hygroscopic. The Contamination of moisture in the fluid as Blaze says causes the Moisture too Boil causing Air Bubbles in the Brake Fluid which then contributes to Loss Pedal. Therefore a Braking Failure. In FAR NORTHERN parts of Australia with High Temps plus Excessive Humidity it pays to Flush Brake Fluids More Regular.
Cheers Kev.
PeterD said
07:02 PM Feb 15, 2016
Dave, what gear were you using when descending the hill?
Jaahn said
08:02 PM Feb 15, 2016
Hi
No need to test the fluid just CHANGE IT. Easy to do and the fluid cost is stuff all. If you do any water crossings then change it soon after as well. Cheapest insurance you can do ! From my observations most fluid is never changed despite the schedule, until some failure forces it. When the pads are changed do not force the fluid back but open the bleed and take the old stuff out as the piston is retracted.
jaahn
hako said
09:27 PM Feb 15, 2016
Testing brake fluid is not a guide to it's effectiveness because you are only testing the fluid in the reservoir, not in the lines and most importantly not at the caliper - the fluid does not circulate.
Only way to make sure is as Jaahn says - change it.
Good Luck.
03_Troopy said
09:33 PM Feb 15, 2016
I might get the air in my tyres tested too, can't be too careful eh... Actually, it should be OK cos I only use Caltex air in my tyres.. I've heard about the shonkey additives from other places.
-- Edited by 03_Troopy on Monday 15th of February 2016 09:35:27 PM
rockylizard said
09:46 PM Feb 15, 2016
Gday...
Ya on the right track there 03_troopy.
When I am not towing I use racing air in my tyres so I can go faster.
When I am towing I use towing air.
I always carry cannisters of the correct rated air to put in my air compressor so that I can correctly adjust my tyres when I am away from the cities.
Cheers - John
03_Troopy said
09:56 PM Feb 15, 2016
Bugger, I didn't know about the racing air
Aus-Kiwi said
10:27 PM Feb 15, 2016
If it's brake fade ? It's the linings getting hot . Or drum expanding when hot . In this case the pedal goes hard and brakes efficiency goes away ..If brake fluid has boiled ? The brake pedal will go to floor and be spongy when they recover ., which will require bleeding to get pedal back to normal .. Yes you should start at the TOP. Of the hill the same speed you intend to be at the bottom . The army teaches that ., brakes should be bleed before each long outing it Atleast once a year .
D and D said
11:46 PM Feb 15, 2016
I was more interested in getting people to have the brake fluid in their tugs tested and, if necessary replaced than in finger pointing exercises.
Yeah, everyone has 20/20 hindsight but that's not helpful when you're confronting this situation in real time.
No, we hadn't slipped into sports mode and locked the gearbox into 1st gear; yes we tried using the manual over ride on the the brake controller with no effect; yes we tried using the park setting on the gear box (with no success); no we don't have a trusted mechanic because we are on the road full time (which is why we use the manufacturers service agent).
While the decision not to shift into manual impacted of the brake failure, contrary to the opinion of some (blaze, Peter), the guy that actually got his hands dirty replacing the brake fluid explained to us that the poor condition of the brake fluid also contributed to the failure.
So next time we're confronted with a steep descent we will slip from automatic to sports shift and lock the ute into low gear. We will also replace the 10" brakes currently on the van with 12" to provide greater braking capacity; but just as importantly, we will be monitoring the condition of our brake fluid more closely in the future as we recommend you do as well.
Regards
Dave
Long Weekend said
12:02 AM Feb 16, 2016
I've been down (and up) Brown Mountain about ten times towing our van, plus an equal number of times solo. Like others have said, I always drop down to the appropriate low gear - at times even 1st. I drive Falcons, first an XE, then an AU and now a BF, all automatics. A lot of people do not know how to use the gears in an automatic transmission - I tell them that is what the gear lever is for! By the way, the engine sure revs in first gear, but as long as it is nowhere the 'red line' it is OK.
Anyway, for those who have never been down that mountain there is a nice coffee shop called 'The Drover's Rest' just as you arrive in Bemboka. Perfect for restoring shattered nerves.
Murray
The Phantom said
12:14 AM Feb 16, 2016
Perhaps the Brown Mountain was named for the colour of the underpants of people descending
The Phantom
D and D said
12:44 AM Feb 16, 2016
The Phantom wrote:
Perhaps the Brown Mountain was named for the colour of the underpants of people descending
The Phantom
I can relate to that. :)
Dave
blaze said
06:03 AM Feb 16, 2016
Hi Dave
Like I said first up I have also done the same. I have been in the trade for 40 years and have seen brake fluid that black and contaminated that its nearly a solid thing and it hasn't created the problem you describe. Has it created other problems, yes. I think your trusted mechanic has told you what you wanted to hear and not been game to tell you that you were too fast for fear of upsetting a client. We all take the easy way sometimes. My answer has been an honest appraisal of what happened to you and also of my own incident.
I have used water as brake fluid in remote outback because of fluid loss and not carrying spare fluid, it works as a temp fix as does milk. So don't believe all that a mechanic tells you
cheers
blaze
Aus-Kiwi said
10:36 AM Feb 16, 2016
Yep I've used ATF to get to next service station and flush, fix and replace wheel cylinder .. The concern is the rust, corrosion in calliper , wheel cylinder you don't see ..
Long Weekend said
10:50 AM Feb 16, 2016
I know it is getting away from the topic somewhat (being checking brake fluid) but for those who have never been down Brown Mountain it is one of the worst in Australia. The descent is ten kilometres long, steep all the way, with many very sharp bends - some limited to 15kms to negotiate.
What is particularly scarey is that if something happens then there is nowhere to go - as D&D Dave found.
On one trip I thought I was being a considerate vanner and pulled over to the side halfway down to let following traffic past. Unfortunately, I was on gravel and the whole lot simply slid. I only just managed to stop before I ran out of road, otherwise I would have had to side swipe one of the passing vehicles.
That said semi trailers use it, while B doubles unhitch the rear, go down, unhitch the trailer then go back up and bring down the rear trailer then reassemble the whole lot. Going up is the same, only in reverse. Makes a trip with a van seem easy!
Last week we traveled from Canberra through Cooma to Bemboka (close to Bega). This involved driving down Brown's Mountain, one of the steepest and windiest pieces of road we've traveled on. This was made worse by road crews repairing a slip closing off one lane with automated traffic lights. The brakes failed when we tried to stop at these lights and we had to proceed through the red light on the wrong side of the road hoping that nothing was coming the other way - fortunately it wasn't.
The cause of the brake failure was overheating and we got the truck checked over as soon as we could. Testing showed that the brake fluid was probably the original brake fluid installed during manufacture and it was in such poor condition that the truck should not have been on the road. This was despite the damn thing being serviced by the manufacturer's agents every 10 000 km as detailed in the handbook which also indicated that the brake fluid should have been replaced at 40 000 km (its done 55 000 km).
The post is not so much to complain about the incompetence of the servicing agents but to get people to get their brake fluid tested and if necessary replaced so something similar doesn't happen to them. I didn't know such tests existed or the consequences of having brake fluid in such poor condition but I do now. It only takes a couple of minutes and could save you your life.
Regards
Dave
cheers
blaze
So if the brakes are used by those vehicles, an offense has been committed.
That would seem to be a good guide for ALL vehicles, not just trucks and busses.
It would seem to me that a light weight vehicle with 3T of van is a disaster waiting to happen.
The cause of Dave's brake failure was overheating, as he said. Nothing to do with brake fluid.
Cheers,
Peter
Brake fluid is hygroscopic ie it absorbs water. This lowers the boiling point of the fluid dramatically and can cause what happened to you. Two things are wrong in your case.
1 Obviously the brake fluid boiled. This was most probably due to absorbing water - see above. It could also be that the service department actually did replace the fluid and that the stuff they used was already slightly contaminated. (I suspect that the fluid was not changed).
2 You probably drove down Brown Mountain without using your gears, or at least not using a gear low enough to hold the load without overloading yoiur brakes. I regularly go up and down the mountain and I barely touch the brakes. OK - I am as slow as a wet week, and at times traffic builds up behind me but as soon as possible I pull over and let them pass. I often smell Fried Ferodo from other cars when I get near the bottom of the hill.Two weeks ago, I went down the mountain with my caravan and I used the brakes only on the hairpin bends. I was taught years ago that if you need 3rd gear to go up a hill, you need 2nd gear to go down it.
Regarding point 1 above, years ago my wife's car was going out of warranty and I took it to the dealer for the last time because I service my vehicles myself. Part of the service was to replace the brake fluid (oddly enough not the clutch). When I got it home, I jacked up the car and checked. Sure enough, the bleed nipples still had road grime on them and not a sign of brake fluid. Straight back to the dealer and asked "Did you replace the brake fluid?" 'Yes Sir' was the reply. Some unprintable response from me evoked action and the fluid was replaced whilst I watched it being done. Your experience was precisely the reason I checked it (plus my mistrust of dealer service anyway). Further, water in the brake fluid can cause corrosion of wheel and master cylinder components. leading to ultimate brake failure. Not good. Manufacturers specify change intervals fro a very good reason.
These days, your local mechanic probably has a fluid conductivity meter which measures the percentage contamination of water in the brake fluid. Maybe you should get someone to check it and if it is high, go straight back to the dealer and (politely) tell them what you think...
Some years ago, I did a driver training course with the Aust Federal Police in Canberra. Fantastic 2 days. One of the questions I asked was "Modern Falcons, Commodores and Magnas all have 4 wheel disc brakes, so braking on modern cars should be no problem" As usual, I was wrong. The instructors said that brakes on modern cars were OK for 1 stop from 100 km/h. They taught us Threshold braking, where you hit the brakes fairly hard and let the car's nose dive. This loads up the front wheels and once the nose has dipped, then you really stand hard on the pedal and wait for a wheel to lock up. As soon as it does, you ease off the pedal slightly until the wheel starts turning again and then load up the pedal again. The stopping distances possible are amazing. Then, they got us into a standard VP Commodore and we started practising threshold braking. After one stop from 80 km/h, it was back up to speed and repeat the process over again. The second stop had the pedal a bit spongy and the third stop the pedal was on the floor. OK - anyone who drives like that deserves to crash into something, but anyone who drives hard down Brown Mountain relying on their brakes is doing similar stuff.
I am not criticising you for running out of brakes - you were probably not aware of the limitations of your vehicle and the road conditions ahead - but it serves as a warning for others to watch out in similar conditions. Well done for alerting everyone to the problem.
In the "good old days" we were taught to go down a hill in the same or one lower gear than that we would need to come up it in. As Peter said if trucks & busses need low gear so does a car towing a caravan.
Something called gravity.
Mike.
Overheating of Brake Disc Pads can be a cause of Brake Failure as also can Overheating Of Brake Fluid that has Absorbed too Much Moisture as it is Hygroscopic. The Contamination of moisture in the fluid as Blaze says causes the Moisture too Boil causing Air Bubbles in the Brake Fluid which then contributes to Loss Pedal. Therefore a Braking Failure. In FAR NORTHERN parts of Australia with High Temps plus Excessive Humidity it pays to Flush Brake Fluids More Regular.
Cheers Kev.
Hi
No need to test the fluid just CHANGE IT. Easy to do and the fluid cost is stuff all. If you do any water crossings then change it soon after as well. Cheapest insurance you can do ! From my observations most fluid is never changed despite the schedule, until some failure forces it. When the pads are changed do not force the fluid back but open the bleed and take the old stuff out as the piston is retracted.
jaahn
Only way to make sure is as Jaahn says - change it.
Good Luck.
I might get the air in my tyres tested too, can't be too careful eh... Actually, it should be OK cos I only use Caltex air in my tyres.. I've heard about the shonkey additives from other places.
-- Edited by 03_Troopy on Monday 15th of February 2016 09:35:27 PM
Gday...
Ya on the right track there 03_troopy.
When I am not towing I use racing air in my tyres so I can go faster.
When I am towing I use towing air.
I always carry cannisters of the correct rated air to put in my air compressor so that I can correctly adjust my tyres when I am away from the cities.
Cheers - John
Yeah, everyone has 20/20 hindsight but that's not helpful when you're confronting this situation in real time.
No, we hadn't slipped into sports mode and locked the gearbox into 1st gear; yes we tried using the manual over ride on the the brake controller with no effect; yes we tried using the park setting on the gear box (with no success); no we don't have a trusted mechanic because we are on the road full time (which is why we use the manufacturers service agent).
While the decision not to shift into manual impacted of the brake failure, contrary to the opinion of some (blaze, Peter), the guy that actually got his hands dirty replacing the brake fluid explained to us that the poor condition of the brake fluid also contributed to the failure.
So next time we're confronted with a steep descent we will slip from automatic to sports shift and lock the ute into low gear. We will also replace the 10" brakes currently on the van with 12" to provide greater braking capacity; but just as importantly, we will be monitoring the condition of our brake fluid more closely in the future as we recommend you do as well.
Regards
Dave
Anyway, for those who have never been down that mountain there is a nice coffee shop called 'The Drover's Rest' just as you arrive in Bemboka. Perfect for restoring shattered nerves.
Murray
Perhaps the Brown Mountain was named for the colour of the underpants of people descending
The Phantom
I can relate to that. :)
Dave
Like I said first up I have also done the same. I have been in the trade for 40 years and have seen brake fluid that black and contaminated that its nearly a solid thing and it hasn't created the problem you describe. Has it created other problems, yes. I think your trusted mechanic has told you what you wanted to hear and not been game to tell you that you were too fast for fear of upsetting a client. We all take the easy way sometimes. My answer has been an honest appraisal of what happened to you and also of my own incident.
I have used water as brake fluid in remote outback because of fluid loss and not carrying spare fluid, it works as a temp fix as does milk. So don't believe all that a mechanic tells you
cheers
blaze
What is particularly scarey is that if something happens then there is nowhere to go - as D&D Dave found.
On one trip I thought I was being a considerate vanner and pulled over to the side halfway down to let following traffic past. Unfortunately, I was on gravel and the whole lot simply slid. I only just managed to stop before I ran out of road, otherwise I would have had to side swipe one of the passing vehicles.
That said semi trailers use it, while B doubles unhitch the rear, go down, unhitch the trailer then go back up and bring down the rear trailer then reassemble the whole lot. Going up is the same, only in reverse. Makes a trip with a van seem easy!
Murray