Hot Brakes

One last thing. You probably won't smell the burning of your own brakes because your are driving away from it. The guy behind you will though!

You can smell your own burnt brakes for days when you do PTI's. I did, the one time I burnt brakes with my trainer. For three days I smelled it clearly. On the fourth day I wasn't sure.

As I said, constant brake pressure is only reasonable when you only need to feather 5-10 lbs pressure on the pads to control your speed. When your transmission, Jakes, or some combination of both is already doing a large part of what is needed to control your speed.

Your quote does not mention jakes at all, nor does it mention feathering.

If you need more than a constant 5-10 lbs pressure to slow the truck, THEN, yes, you stab brake, and allow the brakes to cool between applications. Constant high pressure application of brakes is BAD.

Brakes generate heat based on how much work they are doing. Brakes at 5-10 lbs pressure are doing a lot less work than brakes at 20-50 lbs pressure, so they generate less heat over time.

The brakes do not only cool when unused. They cool constantly, but a little faster when unused. They overheat when work performed by the brakes generates more heat than ambient cooling.

At 5-10 lbs pressure, a braking system will heat up to a point that is not dangerous, and maintain that heat level. This is basic physics, and is not addressed by your article.

FarmerBob...stab braking is not recommended with trucks equipped with ABS brakes. Even so, it's a technique reserved for emergencies and not something that should be used for controlled downgrade operation. If you don't believe me then I highly suggest referencing proper braking techniques in the High Road Training Program.

Second I fundamentally disagree with applying a constant 5-10 lbs of pressure when braking downhill. And use of the word "feathering" to describe a downhill braking technique is best reserved for mountain biking, motorcycles and limousines, not heavy trucks. It doesn't apply.

Snub braking as described in Tractor's article (which was written by a seasoned professional, not a rookie) in combination with intelligent use of the engine brake is the recommended approach for controlled downhill braking. It's also the technique taught when training because it's safer and far easier to learn . Learning how to apply a 5-10 lb continuous brake application for a novice driver requires a student to take their eyes off the road and look at their brake pressure application gauge (upper left on panel of the Cascadia) if they even have one. Teaching this level of finesse IMO is impractical at best and potentially can cause brake overheating if too much continuous pressure is applied.

The technique you described hasn't been widely taught since the early 2000s and has been removed from the CDL manuals and replaced with snub braking. This change was supported by extensive testing by University of Michigan Transportation Research Institute in the late 90s.

The prevalence of any driver using the technique you described can easily be seen by the lack of trailer brake lights continuously lit descending a long downhill grade. I drive in a lot of mountain terrain and never, I mean never see trailer brake lights in front of me continuously lit while I am going downhill.

I do not use your technique or recommend that any one use it (especially when learning). If it works for you, more power to you but you are clearly in the minority and are not controlling your truck any more effectively than if you were using effective snub braking.

Aw my 1st time down fancy gap lol

Especially when your fuel stop is the Love's at exit 1...lol...and your carrying 44k in the box. I've smelt em on that hill too.

Sorry for the confusion earlier. I have always had a difficult time remembering the difference between snub and stab braking terms, though the actions are simple and obvious. One is for oh****! moments, the other is for situations where feathered braking isn't enough braking power.

I can only speak to my own experience, and the experience and instruction of every instructor and trainer I have had. Every single instructor at TDI and at Stevens Transport taught us that if you can control your speed with feathered, constant application of 5-10 lbs pressure, you should. The reason being that it is the safest method, since it is nearly impossible to overheat brakes that way, if you do it right. If you need more than 5-10 lbs constant feathered braking power, then you DO need to start using snub braking.

It does take time to learn to maintain feathered brakes without needing to watch the pressure gauge. However, you better be looking near those gauges regularly anyhow when you are a newbie going downhill, since that's where the speedometer is.

Other people can trot out all the million-miler comments they want. I trust my trainers, but I trust physics more. Physics says that if you can equalize heating and cooling of the brakes with feathered constant braking, it is far safer than rapid heating and cooling cycles by snub braking, because rapid heating and cooling causes a great deal of stress on mechanical systems.

I just had my tractor quarterly inspected after driving it 35K miles. The mechanic told me that he'd never seen wear as even as I have on all ten tires, and all six brake pads. All ten tires were within 1/32 of each other, and he couldn't measure any difference between any of the brake shoes. I do 5x5 braking adjustments regularly, and I almost never snub brake. I have had a single hard braking event since I started driving, including time in trainer trucks.

Just to short circuit most rapid responses, I'll say it again. If feathered brakes between 5-10 lbs constant pressure isn't enough braking, then you DO need to snub brake.

You need not agree with my, but you do need to agree with physics.

Just to short circuit most rapid responses, I'll say it again. If feathered brakes between 5-10 lbs constant pressure isn't enough braking, then you DO need to snub brake.

You need not agree with my, but you do need to agree with physics.

Well, it still kind of sounds like you didn't read what Tractor Man posted. It doesn't disagree with the idea that the same amount of heat is generated whether you ride the brakes or use snub braking. In fact it says that what you do was at one time the recommended method. But according to that article, the problem isn't overheating due to too much constant brake pressure, but the fact that applying low pressure will not apply all the brakes evenly, so some will overheat. If you were taught to do it that way and it's working for you, great, I'm not going to tell you that you should do it a different way. Maybe the fact that you keep everything in adjustment is why it works well for you. But I feel like I learned something valuable from this thread and that article.

Matt...do you think I just make sh** up?

You can argue with the scientists then (I wish you would). They were able to prove over fifteen years ago that there is no evidence supporting less heat buildup using 5-10lb air pressure of continuous braking vs snub braking while ascending a downhill grade. Again please reference the study I replied with conducted by the University of Michigan. Please read it, I wasn't making that up. To repeat, it was used to support a change in the de facto method of controlled downhill braking.

5x5 braking (5 seconds to slow 5 mph) along with being in the proper gear and using the engine brake to control descending speed, by definition is a key component of snub braking. Your addition of 5x5 brake application was not part of your initial reply.

The continuous braking technique you are touting is no where to be found in the current training material.

I am done with this debate Matt. I have offered multiple logical reasons, current DOT guidance and one scientific study that is in conflict with your opinion, yet you continue to argue in spite of everything.

Do what you want, never suggested otherwise. However nothing in your reply offers a compelling reason to adopt the 5x10 lb continuous braking technique nor does it address the difficulty in learning it.

Just to short circuit most rapid responses, I'll say it again. If feathered brakes between 5-10 lbs constant pressure isn't enough braking, then you DO need to snub brake.

You need not agree with my, but you do need to agree with physics.

Well, it still kind of sounds like you didn't read what Tractor Man posted. It doesn't disagree with the idea that the same amount of heat is generated whether you ride the brakes or use snub braking. In fact it says that what you do was at one time the recommended method. But according to that article, the problem isn't overheating due to too much constant brake pressure, but the fact that applying low pressure will not apply all the brakes evenly, so some will overheat. If you were taught to do it that way and it's working for you, great, I'm not going to tell you that you should do it a different way. Maybe the fact that you keep everything in adjustment is why it works well for you. But I feel like I learned something valuable from this thread and that article.

Thank you Kurt! Obviously you READ and comprehended the article. I learned some very valuable information from it myself. I certainly DON'T have all of the answers, that is why I look them up and TRY to deal in FACTS.

Matt...do you think I just make sh** up?

You can argue with the scientists then (I wish you would). They were able to prove over fifteen years ago that there is no evidence supporting less heat buildup using 5-10lb air pressure of continuous braking vs snub braking while ascending a downhill grade. Again please reference the study I replied with conducted by the University of Michigan. Please read it, I wasn't making that up. To repeat, it was used to support a change in the de facto method of controlled downhill braking.

5x5 braking (5 seconds to slow 5 mph) along with being in the proper gear and using the engine brake to control descending speed, by definition is a key component of snub braking. Your addition of 5x5 brake application was not part of your initial reply.

The continuous braking technique you are touting is no where to be found in the current training material.

I am done with this debate Matt. I have offered multiple logical reasons, current DOT guidance and one scientific study that is in conflict with your opinion, yet you continue to argue in spite of everything.

Do what you want, never suggested otherwise. However nothing in your reply offers a compelling reason to adopt the 5x10 lb continuous braking technique nor does it address the difficulty in learning it.

5x5's are not a braking method (that I have ever heard of.)

5x5's are how you adjust your brakes manually. With full pressure in tanks, and with tractor and trailer brakes released, push the service brakes all the way down, and let them stay at maximum pressure five seconds. Repeat five times. If your brakes are not properly adjusted, and the automatic adjusters are working properly, the 5x5 will adjust your brakes. You will hear something that almost sounds like a very tiny air ratchet coming from under your truck if adjustments are happening. If you do hear that noise, keep doing 5x5's until the noise stops.

In the articles I just read, improper functioning of the braking system is most of the logic behind using snub braking when you could be using feathered braking at low constant 5-10 lb pressure. If your brakes aren't adjusted right, you shouldn't even be rolling on them, never mind rolling downhill.

I'll agree to disagree on the rest.

5x5's are not a braking method (that I have ever heard of.)

I've never heard it called that but that was the method they taught when I went to school in 1993. At the time they said that light steady pressure was acceptable, but light snub braking was preferable. So it's certainly not new.

You need not agree with my, but you do need to agree with physics.

Which findings are you citing? Do you have actual data from a study to support what you're claiming so we know there isn't a difference between your physics and actual physics?

Like I said I'm done.,,my mistake on the 5x5...I scanned they reply and didn't see the word adjustment. That I am sorry for...

Just to be clear Matt snub braking includes the following:

Being in the proper gear, proper use of the engine brake and applying the service brakes to slow the downhill speed by 5 mph and then release is the definition of snub braking.

You want to disagree with that, on you. You want to disagree with DOT on you. You can argue with Brett now, my popcorn is getting cold. Done...