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Old 01-18-2021, 07:43 PM   #21
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Its not that you can't downshift with the AT545, its just that you don't have *as good* of engine braking since you do not have the lockup torque converter. Instead of the direct mechanical connection, you only have the "fluid coupling" in the 545...

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Old 01-18-2021, 11:33 PM   #22
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Was leaving Keystone SD. after Sturgis heading to the airport in Rapid City and was going east down a 15% grade, no matter what I did to prevent it I had no brakes by the time I was at the bottom. No, gearing down just made the engine over rev. so I had to pump the brakes to keep the revolutions down. The rest of the family was in a rented van in front of me and the CDL O/O truck driver driving the rental said he was waiting for me to tap him in the rear and he would do what he could to slow me down, luckily that didn't happen and the bottom gradually leveled out and I could coast for a while to get the brakes cooled down, it was smelly and there was brake dust everywhere. To answer and unanswered previous question: no pulling your Ebrake will do nothing if your air brakes are already hot but if you have a drum brake on your transmission it may give you another 5 seconds to pick your choice of death.
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Old 01-19-2021, 12:21 AM   #23
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Quote:
Originally Posted by Ronnie View Post
I have to say I do not understand why it is said you can not downshift an AT 545. It shows on the gear shift lower gears will it not allow a lower gear even though they are shown on the gear shift?


My 89 Dodge with a cummins had the 727 automatic. Three speed, no lockup converter. Great trans could take anything that engine put out, and I had it turned up pretty good. Long mountain grades I would drop it in 2nd and it would hold back nicely with heavy trailers in tow. The torque converter does not freewheel, as long as you are above stall speed.


So it would seem to me that with the 545 you should be able to do the same.


With the 545 are you going up in high gear or has it downshifted? if it has downshifted to go up the hill/mountain then select that same gear it downshifted to for coming back down the hill/mountain.

From my TC1000/TC2000 owner's manual, pages 65 & 66:
Quote:

ALLISON AUTOMATIC TRANSMISSION
AT 545
The Allison transmission provides four forward speeds and one reverse. Selective control is obtained
through the selector lever located on the right area of dash. The selector lever must be in N (neutral) to start
the engine. If the engine starts in any other position, the neutral start switch is malfunctioning. Use D for all
normal driving conditions. The vehicle will start in first gear and as you depress the accelerator, the transmission
will upshift to second, third and fourth gear automatically. As the vehicle slows down, the transmission will automatically downshift to the correct gear. Use (3&2) when the road load or
traffic conditions make it desirable to restrict the automatic shifting to a lower range.
When the conditions improve, return the range selector to the normal driving position.
These positions also provide progressively greater engine braking power (the
lower the gear range, the greater the braking effect). Use (1) when pulling through
mud and snow or driving up steep grades. This position provides maximum engine
braking power. Use R (reverse) for backing the vehicle. The vehicle should be completely
stopped before shifting from a forward gear to reverse. Reverse gear provides
the greatest tractive advantage.
CAUTION: In the lower ranges (1, 2 and 3) the transmission will upshift above the
highest gear selected when the recommended engine governed speed for that gear is exceeded.
Thanks for making me look this up. I remembered the CAUTION part at the end, but not the "you can downshift for greater breaking effect" part just above that.
Never-the-less, there is a big hill in Eugene that leads up to a big peak at the edge of town where you can hike. I went there often. The hill is very steep. I barely make it up in first gear. When I tried downshifting to go downhill, that didn't work for the CAUTION reason listed in the manual: my motor quickly hit the 2500 or 2600 (or near) RPM mark, and the tranny upshifted.


not sure what speed 3rd gear would decide to shift into 4th, or 2nd into 3rd, but I think now I will be trying that on the highway - along with brakes - and see what happens.



It was a long day, it's late, tomorrow is another long day for me [it's been dry! for 10 days, and my wooden deck is now dry enough to throw down a steel drip-pan to catch sparks (and any drips), and weld, since that is where my 20-amp outlet is - third day since last June that I could weld.]


So I'm gonna split my further replies into two parts, and also do some more research and get me a real college degree in Newtonian Physics and Rocket Science from the Wikipedia University of Fine Arts and Technology - no more of this high-school-dropout level Math.


Anyway, I made my first post specifically to create a controversial conversation (not an argument, thanks for keeping it that way!), and for two reasons:


#1: to keep this thread fresh so more newbies will see it and get the hint of what we all do agree on: SLOW DOWN at the TOP of the hill and proceed down the hill slowly. This is so paramount.


#2: I do think there is a mis-understanding here, and although I believe it lies with the "general public", I'm fully open to being wrong, and if I am, I want to know WHY I am wrong (cause I'm one of those guys), and not just because "the book says so". WHY does the book say so?


Furthermore, I put the "I'm so smart" statement, implying "you should listen to me" as bait that I'm glad no one took. Since I got here years ago I've been bashed for BS - the first was for hanging my curtains with little neodymium magnets, in little pockets that I sew in the curtains, and retain with a safety pin for removal to wash. (nothing is better for ME in MY opinion) I've had my creed insulted. I've had my family insulted - people the insulter never met! I've recently seen arguments over BS on other threads.
I like the by-line someone on this site has:
Don't argue with stupid people: they just drag you down to their level and beat you with experience.
That is what I'm talking about.


All the replies so far on this thread, even the ones I disagree with in technical terms (but DO agree with in principle - see below), are good, honorable, and intelligent replies, methinks.


Continuing on, I don't mean to imply that the DOT-CDL books are wrong in principle, and definitely don't mean to imply that people should ignore them. Rather, I hope to show (since I've failed to so far) to the "general public" that the "assumed" facts behind the principle are wrong; OR I hope someone else can point ME to the "source" that lists and/or explains these facts; OR I hope someone "smart" can show me how my math (to be presented) is wrong. And, after attempting to show that the "assumed facts" are wrong, I want to present outright guesses as to other reasons the books say what they do - very good reasons I see.


The people who create DOT ratings are smart people - I bet many smarter than me - and far more on-the-ball, educated, and experienced in the math behind the Newtonian physics that govern bodies in motion. Over the years they have added fail-safe after fail-safe practice to their recommendations. They know how to rate the gross vehicle weight based on the suspension and size of the brakes, and how to correspond the limits they impose there with speed limits on down-hill grades, and they are NOT going to allow a situation where brakes are going to overheat in a properly "legally" loaded vehicle going the speed limit. BUT IF YOU CAN DOWNSHIFT AND LOAD THE ENGINE TO SLOW - THAT IS MUCH BETTER than riding your brakes, or "pulsing" them.



Sure Brad had that time back in 1973, and he admitted that, like I said, the vehicle was underrated for the load - indeed sounded underbuilt. they've focused more on safety safety safety since then as traffic is growing exponentially.



The "drivers books" say I should put both hands on my little car's steering wheel, at the 10:00 and 2:00 positions. If I only use one hand, am I destined to crash? In fact, I can drive my cars/pickups with my knee, and even turn using both knees - I trained myself to do that when I was 16 (and traffic was WAY less). Driving my bus, I do use 2 hands, and also never look away from the road for even 1/2 second - as I would in my car to change the radio or something. And driving my bus with my knee would be insane!

I have ALWAYS applied a continuous brake on a hill when I drive. Yea, I heard the "pulse" theory when I was 15 and learning. I live in a very hilly area - some of the most steepest hills in the country. Every day I drive down one of the highest, steepest. I ride my brakes at 10-20 mph in my bus, 20-25 mph in my car, every time. I would find it weird to slow down to 5mph and then back up to 15mph in 3-5 seconds, and then back down to 5.... And I never had a problem.

I hope to show in my next post, in generalized mathematical terms, that the basic First Law of Thermodynamics plays a part in what I'm saying. Energy can not be created or destroyed, only converted. Inertia plays a part. Gravity plays a part.


Anyway, I'm about rambled out, and too tired to make a good mathematical argument. See ya soon....
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Old 01-19-2021, 12:44 AM   #24
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FROM THE BLUEBIRD OWNERS MANUAL:
pg. 56:
Quote:
USING ENGINE AS A BRAKE
In descending a steep or long grade it is a good practice to use the engine as a brake to retard vehicle
speed. Reduce speed before the grade and shift into a lower gear (with either automatic or manual transmissions),
being careful to select a gear which will slow the vehicle without overspeeding the engine. Under such
conditions, use the brakes sparingly to prevent them from overheating, which reduces brake effectiveness.
WARNING: Do not take transmission out of gear when going down a steep or long grade. You may not be
able to get the transmission back in gear, and the drastic slowing of engine speed could reduce air pressure
supply to the air brake system, and result in a reduction of brake capacity.
pg 68:

Quote:
USING THE ELECTRIC RETARDER (TCFE)
The electric retarder control switch is mounted on the vertical panel to the left of the driver. It has five
positions (one off and four retard positions). Each higher number increases the amount of retardation
to slow the vehicle.
Remember the retarder is a vehicle slowing device, not a stopping device. Final stopping must be
accomplished by applying the service brake.
Always release the accelerator completely before applying the retarder.
Do not use the retarder when road surfaces are slippery. Minimum applications of retarding effort
must be the rule.
Consult the retarder manufacturer's owner/operator manual for additional information.



DOWNSHIFT CONTROL AT 545
The transmission can be downshifted or upshifted, even at full throttle, and although there is no speed
limitation on upshifting, there is on downshifting and reverse. Good driving practices indicate that downshifting
should be avoided when the vehicle is above the maximum speed attainable in the next lower gear.
Therefore, good driving habits have been designed into the Allison transmission shift pattern. The downshift
inhibitors within the valve body prevent those harmful shifts when the vehicle is going too fast for the next
lower gear.
If the downshifts are attempted at excessive speeds, the inhibitors prevent the selected downshift until
the vehicle reaches an acceptable speed.
pg. 69:
Quote:
USING THE ENGINE TO SLOW THE VEHICLE
AT 545
To use the engine as a braking force, shift the range selector to the next lower range. If the vehicle is
exceeding the maximum speed for a lower gear, use the service brakes to slow the vehicle to an acceptable
speed where the transmission may be downshifted safely.
An automatic, compared to a manual, shift transmission has a longer coast down time. Until you are
accustomed to this characteristic, you may need to manually downshift to reduce speed.
With a little experience in driving the automatic, you will learn to decelerate a bit sooner, or brake until
automatic downshifts occur. This will reduce the need for manual downshifting.
Somewhere I read how this tranny likes to stay in gear longer than usual before upshifting or downshifting, which makes the stop-and-go for kids smoother, and driving in traffic smoother. Just can't find it...
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Old 01-19-2021, 01:54 AM   #25
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This is my office every day. heavy trucks, steep mountains and the sh*ttiest conditions. This is the Coq (Highway Thru Hell) I know what works for me and it works for everyone else if applied right. Im not here to debate this any further but a big beef I have is your very first response to the OP was not accurate but stated like you knew the answer, only later revealing that in fact you are not a commercial operator and have little experience in this matter. This does a great disservice to the new members and new drivers and is dangerous. How about next time start your response with
"hey I'm not a commercial driver and don't have an air brake endorsement but my opinion is"
Stay safe

Oscar
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Old 01-19-2021, 06:53 AM   #26
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Thanks for the quote out of the 545 manual. I was not aware that even if lets say you selected 3rd before going down grade that it would shift to 4th if the engine revs exceeded max. That would scare even me, and I am hard to scare. So in this case I would say be real careful about engine rpms so a surprise upshift does not catch you in bad spot.


My old Dodge with the 727 would not go up to a higher gear then selected no matter engine rpms.



As far as staying on the brakes lightly for a long time or "stab" braking. Theoretically it would make the same heat overall either way. But you have cooling time in between applications with stab braking.



By the way on trains we set the brakes, even retain then meaning that each car can be set to a certain minimum so that if the engineer release all brakes then actually stay on some, hence the word "retained". This is done to preserve air. On our little short line we will set some hand brakes for one descent we have that is about 3miles long.



I tend to drop only a few mph each application of brakes. I do know how my bus handles grades so can be in a good gear most of the time to hold it back with little or no brake use. Having a manual trans helps, plus ten gears to choose from helps.
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Old 01-19-2021, 07:09 AM   #27
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Quote:
Originally Posted by BeNimble View Post
You might carry an anchor with a short chain..works for boats.
A big one would work.

Ahhh so thats what the "master cancel" button is for
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Old 01-23-2021, 04:19 PM   #28
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https://wanderlounge.net/wp-content/...8/07/PI221.pdf

Heat causes expansion also causes gas build up on the friction material surface. So less friction material contact means faster wear,faster brake fade and more heat building up quicker. The last one is hard to understand but it is the truth. Less lining to dissipate heat back into. So the leading edge of the lining holders all the heat.
Improperly adjusted brakes ( and if you have air brakes and dont know how to adjust them? learn to. sell it or pay someone to keep them in you top working order ) even automatic slack adjusters do NOT work well enough all the time.
All this advice is great

Use a lower gear or two
Maintain to a lower speed

The air brakes need to be adjusted correctly for any of this to work.
Surprised the wanderlodge website had that.

I to hold a cdl and drive steel and equipment at 80k plus.
Learn how to check and adjust your brakes.
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Old 01-23-2021, 06:42 PM   #29
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One of the rules of old truckers is to never start down the hill in a gear higher than what you climbed that same hill.
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Old 01-23-2021, 07:55 PM   #30
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I would only use this as a dire last resort but an old co-worker of mine faced just that situation back in the 50's or 60's coming down from Pike's Peak (or somewhere close by). He suffered a total loss of brakes and was beginning to gain speed at an uncomfortable rate. I suppose that he had already used the emergency brake or perhaps the brake pads had glazed and become ineffective. He shifted into reverse and by modulating the throttle gradually slowed the vehicle down by using the automatic transmission as a braking force.

I have never tried this and won't unless I too am in such a dire circumstance. I also have never forgotten how shocked I was when he told me about doing this but after listening to him and trying to find any other way I decided to file this away in my memories just in case.

Maybe no one will ever need to try this but it just might help someone regain control enough to safely stop their vehicle.
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Old 01-23-2021, 07:56 PM   #31
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if no jake/engine brake, drop one gear before heading down a big hill. do not let the RPM'S go past half way between idle and redline. if the RPM'S head towards the redline, slow it down with the brakes and drop another gear. it is easy to scrub off 5mpg at 40 then at 80...at 80, it is all over anyway.

Disk brakes, which do not need adjustment, work so much better than drum brakes on big trucks. I have them on my tractor, which is at about 120,000 LBS every day. While some newer buses might have them, most older buses do not. So you need to learn how to adjust them.

My rules of thumb for the trailers I pull is 1/4 to 1/3 turn on the adjuster nut. Lost already? It is very easy to adjust brakes once you know how.

If you don't know how, your brakes probably need adjustment.
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Old 01-23-2021, 09:51 PM   #32
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My suggestion FWIW is to retrofit a supplementary brake on your bus if you drive a lot in the mountains. Telma (and other brands) electro-magnetic retarders work VERY well (they have been universally used in Europe for many decades) and come in different flavors to fit almost any drivetrain. Williams (and other brands) exhaust-restriction brakes work moderately well, but not as well as Jacobs ("Jake") engine compression-release brakes and Telmas. Whatever you do, always have a solid Plan B when descending any steep and/or long downgrades.

Even with a non-lockup transmission like the infamous AT545 you should still have a reasonable amount of engine braking available. Many years ago I had a Mercedes-Benz 280SEL, one of the timeless W108 sedans, which had the K4C25 transmission that had no torque converter or lockup, just a very tight fluid coupling, and it gave me as good downhill control as a manual transmission. At worst, non-locking transmissions will require you to descend in a gear or two lower than a locking transmission, but who cares? It's a bus, so just take your time, put on the four-way flashers, and enjoy the scenery.
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Old 01-24-2021, 12:08 AM   #33
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There's been a lot of good things discussed already.

To the OP: in the event of air loss, the air brakes will TRY to take care of themselves by applying the rears when the air pressure isn't sufficient to overcome the springs. Pulling the parking brake is in effect the same thing. Depending on the speed/weight/grade, the attempt might stop you. It's not super advisable because if the wheels lock controlling the vehicle can be, well, difficult. In the event of overheating, you're left with the engine braking (which on a diesel without a compression brake or exhaust brake is not as strong as a gas engine since there's no throttle plate choking the engine--regardless of loose/no lockup torque converter), obstacles, and runaway ramps. The ramps will stop you but will take a hefty toll on your bus and wallet. Overall, start slow and try to stay slow. If it feels like you're traveling too slow down the hill, you're doing it right. In reality, you should try to set your speed/gear selection at the top of the hill so that your primary braking is the engine holding you back and the regular service brakes are the "emergency" brakes if you get going too fast--not the other way around. Admittedly, a setup like a non-braked diesel with an AT545 has some limitations when it comes to engine braking (already discussed in the owner's manual quotes), driving just requires a different approach. A bus, or any other big, heavy vehicle, isn't a sedan and can't be driven the same way. Fortunately for a lot of us, we're underpowered for the climb up the hill, so cresting nice and slow works out well if you keep it slow on the way down.

On the topic of overheating brakes, while the total friction/heat generated going down the hill is the same (for a given speed), the brakes are better able to dissipate the heat with cycled braking. Yes, pads/shoes will glaze over, but "brake fade" actually has more to do with the drums. When drum brakes (more common on busses and CMVs for many years) are applied, the friction lining of the shoes actually heats the drums which in turn attempt to dissipate the heat to the air/wheel/axle/whatever it can--the shoes aren't what dissipates the heat. As the drums heat up, the diameter grows (this is where all the slack adjuster talk becomes relevant) and the shoes have to be actuated farther to maintain pressure against the drum. Eventually, if the drum grows too large from too much heat, there's just not enough travel in the shoe actuation to press anymore against the drum and the brakes begin to "fade". So while it's true that the shoes actually stay really close to the drum, that's only the case when the properly adjusted brakes are cool. As they heat up, the clearance increases and some air could snake past the baking plate to cool the linings--but it's still the drum that's the key. One reason that drums have a maximum allowable diameter when turning them has to do with the shoe actuation travel. Other reasons include reduced strength/heat capacity (don't want them to burst either). Disks and pads are less susceptible to fading since the calipers are attempting to squish the disk vs expanding a drum.

Now, the reason that the cycled braking works better can be easily illustrated with cooking. If you've ever cooked with an oldskool, cast iron pan, you'll know that it takes a while to heat it up and a while to cool down. Brake drums (heavy and usually cast iron) act the same. When you apply the brakes, the drums absorb heat like a sponge. When you let off, the heat drips out--and you have to give it some time to drip out because you can't wring it out like you could a sponge. If you're riding the brakes all the way down and constantly putting heat into them, you can get to the point that you're putting the heat in faster than the drum can leak it out to the atmosphere--just like a sponge under a constant faucet gets saturated and can't soak up anymore water. Some old trucks actually had water tanks with drains that the driver could open up to flood water over the drums to cool them off (since water can absorb heat faster than air) if they got hot.

Another note for people thinking that a locking torque converter will solve the problems, many automatic transmissions unlock the converter when coasting or when not in highest or second to highest gear. If you've geared down appropriately, there's a good chance you're not even in lockup anyway. I don't like my AT545 (RoadRanger in the works), but engine braking isn't that bad--there's other problems like low top speed and poor hill climbing that make it less than ideal. But, at the same time, I can't get mad at it for choking when I'm asking it to do things it wasn't designed to do, haha.
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Old 01-24-2021, 11:25 AM   #34
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I feel your heat! We have a 32' flat nose and tow just under 7000k on the trailer and have frightened our selves up and down just about every hill the Continental Divide has to offer. First, I'm going to invest into an Exhaust Brake. Second, there is no shame in dropping into 2nd and putting on your 4-ways as a slow warning while going down. If you can equal your On Brake time with same or greater Off Brake time, you have a better chance of making it to bottom with non smoking brakes. Gravity is foreboding when weight is helping.
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Old 01-24-2021, 11:29 AM   #35
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Quote:
Originally Posted by Brad_SwiftFur View Post
Sorry to disagree, but as a professional driver, and speaking from my own personal learning experience, you *WILL* overheat the brakes by riding them down a mountain, even at a low speed (yes, I learned this The Hard Way!) The correct way is to let the vehicle 'engine brake' and when it reaches max RPM, apply enough brakes to slow down 5-10 MPH, rinse and repeat. If you find yourself using the brakes excessively, then you are in too high of a gear, you need to gear down and slow down. This does in fact allow some time for the brakes to cool between uses.

.
also called stab braking and taught in professional driving schools and community collages with cdl programs. (that would be a good source)
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Old 01-24-2021, 11:55 AM   #36
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Quote:
Originally Posted by Johnny Mullet View Post
NEVER ride the brakes. Coast downhill and when the speed gets uncomfortable, hold the brake down and slow to a lower speed. Let it coast and repeat as needed.
I'll second this.

When we made the trip from NH to KY, we went through MA, CT, NY ( RT 287, RT 78 ), PA ( RT 78, RT 81 ), MD ( RT 81, RT 70, RT 68 ), and WV ( RT 68, RT 79 ). Routes 287, 78 and 81 all had fairly hard ascents where we slowed to 35MPH, 45MPH. When going downhill, if it were daytime with full visibility sometimes I would coast up to 70-75 MPH, and then pulse the brakes down to 50MPH (or not brake at all if I could see I was just going to be going straight back uphill shortly). Most of the time, or at night I would coast up to 55 MPH, pulsing down to 45MPH.

The hardest descent for our trip was in WV on RT 68. There was a mandatory truck stop for checking brakes and I took advantage of it to do a walk around prior. I kept in the slow range despite good visibility (braking at 55MPH down to 40MPH), put my hazards on. The whole way down I smelled burning brakes, most likely not my own.

Especially if you are in a larger bus, when doing big hills you are going to be worried about being able to slow down. Do not drive like you are in a car, if you want to get somewhere as quickly as possible you should first make sure you arrive at all. Be in good shape mechanically, go slow on anything other than a straight road with clear visibility measured in miles, and make sure all your lights work and use them.

To answer the OP, echoing others here if you lose pressure the brakes will engage. Pull over as soon as possible.
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Old 01-24-2021, 01:15 PM   #37
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You don't need to get an air brake endorsement. just do the tiny home work(lol) and get the knowledge. if you get a CDL which is what you would need to get that endorsement, it will put you at greater risk of higher fines from the po po.
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Old 01-24-2021, 01:55 PM   #38
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Quote:
Originally Posted by Arumrill1 View Post
You don't need to get an air brake endorsement. just do the tiny home work(lol) and get the knowledge. if you get a CDL which is what you would need to get that endorsement, it will put you at greater risk of higher fines from the po po.
I completely agree about learning as much as you can about air brakes...how they work, how to check them for proper adjustment and function, etc. Much of that can come from videos and online guides.

And, true, a CDL isn't necessary once your bus is registered as a motorhome or RV. But it wouldn't hurt to read the CDL manual I posted a link to. I do, however, disagree about the higher fines. Yes, the fines are higher for commercial vehicles...but in your RV/MH the fines are the same regardless of your license class. At least they are in every jurisdiction I've seen. As a retired "po po", who's been through CVI training and worked with officers in (and from) many other states, I've not seen different fines based solely on the class of license. It might even get you a discount on your insurance and, of course, it's technically illegal to drive a registered bus without a Class B...which could limit your ability to pick up some auction-purchased vehicles.

Regardless of whether a skoolie owner chooses to get a CDL or not, I think it's important for every bus operator to get educated and think/drive like a professional bus driver.
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Old 01-24-2021, 07:34 PM   #39
Mini-Skoolie
 
Join Date: Jun 2018
Posts: 26
Quote:
Originally Posted by kazetsukai View Post
I'll second this.

When we made the trip from NH to KY, we went through MA, CT, NY ( RT 287, RT 78 ), PA ( RT 78, RT 81 ), MD ( RT 81, RT 70, RT 68 ), and WV ( RT 68, RT 79 ). Routes 287, 78 and 81 all had fairly hard ascents where we slowed to 35MPH, 45MPH. When going downhill, if it were daytime with full visibility sometimes I would coast up to 70-75 MPH, and then pulse the brakes down to 50MPH (or not brake at all if I could see I was just going to be going straight back uphill shortly). Most of the time, or at night I would coast up to 55 MPH, pulsing down to 45MPH.

The hardest descent for our trip was in WV on RT 68. There was a mandatory truck stop for checking brakes and I took advantage of it to do a walk around prior. I kept in the slow range despite good visibility (braking at 55MPH down to 40MPH), put my hazards on. The whole way down I smelled burning brakes, most likely not my own.

Especially if you are in a larger bus, when doing big hills you are going to be worried about being able to slow down. Do not drive like you are in a car, if you want to get somewhere as quickly as possible you should first make sure you arrive at all. Be in good shape mechanically, go slow on anything other than a straight road with clear visibility measured in miles, and make sure all your lights work and use them.

To answer the OP, echoing others here if you lose pressure the brakes will engage. Pull over as soon as possible.
#1rule is you can go down hill to slow as many times as you like but you only get to come down to fast once. Pakbrake makes a good exhaust shutter brake that should be available for most diesel powered buses.
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Old 01-25-2021, 04:22 PM   #40
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Join Date: Feb 2020
Location: Larchmont NY
Posts: 72
Engine: Mountains, highways, east to west coast capable
Rated Cap: Wheelchair lift ~34c 24a
Quote:
Originally Posted by rossvtaylor View Post
I completely agree about learning as much as you can about air brakes...how they work, how to check them for proper adjustment and function, etc. Much of that can come from videos and online guides.
......

Regardless of whether a skoolie owner chooses to get a CDL or not, I think it's important for every bus operator to get educated and think/drive like a professional bus driver.
I passed my NY Class B CDL this morning with the Schoolbus endorsement. I mentioned more on my decision to get the CDL elsewhere in the forum. Im a good, reasonably conservative driver, and there is no way I would have routinely taken the time for a full precheck (or really learned it). Getting the CDL [U]made[U] me learn how to do things the safest way. Id like to add that I have 100 times more respect for big rig drivers than I have ever had.

Now I just need to get my AZ bus to start when its cold.

Barbara
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