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RBrian
Senior Member

United States
71 Posts

Posted - 02/09/2011 :  06:52:25 AM  Show Profile  Visit RBrian's Homepage  Reply with Quote
Looking at getting air disc brakes on new C2 bus purchase. Is anyone here familiar with these type brakes on a school bus. If so what do you think of them. Are they worth the up charge or not?

BJ Henderson
Advanced Member

USA
280 Posts

Posted - 02/09/2011 :  07:40:25 AM  Show Profile  Send BJ Henderson an AOL message  Reply with Quote
I've worked on fleets that have used them on commercial trucks. They cost a lot more to maintain than air drum brakes. Components are more complicated and have more moving parts to fail. Plus those parts are heavy and cumbersome to change. Parts avaliability is also an issue.
If they are in an environment where fins on the brake rotors get plugged, rotors will need to be changed on most every brake job.

I do not see a real advantage of having them, considering all factors.

CMTT,CMAT,CMBT
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RBrian
Senior Member

United States
71 Posts

Posted - 02/09/2011 :  09:58:37 AM  Show Profile  Visit RBrian's Homepage  Reply with Quote
BJ, thanks for your input. I have read that newer air disc don't have the issues they had 10 or 20 years ago. The sales pitch is they last longer and cost less than drum brakes to maintain.
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JustinB
Advanced Member

United States
490 Posts

Posted - 02/09/2011 :  10:05:10 AM  Show Profile  Reply with Quote
Aftermarket parts supply is still limited & they outboard drums are still much easier to service.
The greatest challenges facing air disc brakes are
- aftermarket distribution (lack of channels & parts availability)
- Rotors are still inboard with 2 basic designs
....R&R the wheel seal
....another 10 bolts to undo & retorque
- The ABS tone-ring is still within 2" of a MAJOR heat source & has no plane break to dissipate.

2 things need to happen for air-disc brakes to become viable
- competitive aftermarket pricing & availability for service parts
.....rotors, "calipers" etch
- Outboard of hub design

I may not know the answer but I can usually find who does.
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Wolf0r
Top Member

USA
2181 Posts

Posted - 02/11/2011 :  1:31:47 PM  Show Profile  Reply with Quote
What options are availabe on a C2 in brakes?

“The good thing about science is that it's true whether or not you believe in it.”
Neil deGrasse Tyson
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RBrian
Senior Member

United States
71 Posts

Posted - 02/14/2011 :  03:28:10 AM  Show Profile  Visit RBrian's Homepage  Reply with Quote
quote:
Originally posted by Wolf0r

What options are availabe on a C2 in brakes?


Bendix ADB-22X air disc brakes is the option I'm looking at. From what I have read searching the web the rotors should last the life of the bus. The pads are available at the dealer for around $80. If the rotors, caliper and pins hold up as advertised, this option would pay for it's self over the life of the bus.
Does anyone here have these brakes? I sure would like to hear what you think of them.
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JustinB
Advanced Member

United States
490 Posts

Posted - 02/14/2011 :  06:28:37 AM  Show Profile  Reply with Quote
Maybe a time for a rethink on my part.

Web page
http://www.roadranger.com/Roadranger/productssolutions/brakes/airdiscbrakes/index.htm

PDF Brochure Link
http://www.roadranger.com/ecm/idcplg?IdcService=GET_FILE&dID=269961

I may not know the answer but I can usually find who does.
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wagonmaster
Top Member

USA
2298 Posts

Posted - 02/15/2011 :  10:27:58 AM  Show Profile  Reply with Quote
I am familiar with them from Line Haul trucks of 25+ years ago,and they worked very well and were easier/faster to reline than drum brakes, especially on a drive axle. Drivers reported that stopping distances were somewhat shorter and less fade on mountainous roads. Rotors were good for several relines (pad changes) without being warped or out of round. New ones, I'm told, are much better and more reliable than those. That said, I would try them on one or two buses where brake applications were more frequent (in town routes) to see how they do before fitting all buses on one purchase with them.

Joe
Land of the Free, because of the Brave!

Edited by - wagonmaster on 02/15/2011 10:29:52 AM
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BJ Henderson
Advanced Member

USA
280 Posts

Posted - 02/15/2011 :  2:30:19 PM  Show Profile  Send BJ Henderson an AOL message  Reply with Quote
Price check an S cam against a calpier assembly. Also see who has one on the shelf for yo

I worked in the waste management business for over 10 years, we had trucks that made upwards of 500 brake applications daily...we tried the air disc brake systems, we also retrofitted the trucks that had them, company wide, as they did not provide the service life, nor service drum brakes did. Those trucks perform what is called "severe duty" and as far as I'm concerned, if it ain't good enough to haul garbage, it sure ain't going on one of our school buses!

Other than that, hey, they are the best thing since sliced bread!

CMTT,CMAT,CMBT
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RBrian
Senior Member

United States
71 Posts

Posted - 06/13/2014 :  03:34:02 AM  Show Profile  Visit RBrian's Homepage  Reply with Quote
Well we have been running 16 2012 buses with air disc brakes for 3 years, 23 2013's for 2 and 23 2014's over this last year.
Pros> Bus stops much better than drum brakes. Pads take 15 minutes to change out.
Cons> We're averaging 30,000 miles on the pads front and rear. Pads cost $200 not $80. Have had to replace 19 calipers under warranty. Calipers cost $1,000. Have had 10 LR calipers lock up. None on the right side. Wheel end gets so hot the ABS light comes on because the sensor is melted.

Bendix rep tells me that there was an "improvement package" that started in 7/2012 that should cure the issues with the caliper sticking. all our 12's and 13's were built before that. Have had no problems with the 2014 yet and pads do seem to be wearing better. Will have to wait another year and see what happens.



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Fastback
Top Member

1500 Posts

Posted - 06/13/2014 :  05:56:06 AM  Show Profile  Reply with Quote
Well I hope they are getting the "bugs" out of them, sounds like we won't have much choice in a couple years.

Why yes, the ORIGinal CHARGER is a Fastback
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Mechan1c
Top Member

USA
853 Posts

Posted - 02/22/2018 :  2:33:02 PM  Show Profile  Reply with Quote
That does not like something to click on...
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bwest
Administrator

United States
3820 Posts

Posted - 02/22/2018 :  2:56:01 PM  Show Profile  Reply with Quote
Thanks for the heads up! It's been deleted. Headed for his other post now and then him.

Bryan
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 02/22/2018 :  3:50:31 PM  Show Profile  Reply with Quote
More spam on this thread? Last two mornings I've had to delete it from here. Wonder what it is about this one that gets it picked?
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 02/23/2018 :  02:50:59 AM  Show Profile  Reply with Quote
Stephendup was back on here again this morning with spam. I locked him out 2 days ago, yet he was unlocked and able to post again. If anybody else sees him, post there so Admin and have a look-see into how he's getting unlocked.
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RBrian
Senior Member

United States
71 Posts

Posted - 02/23/2018 :  05:47:13 AM  Show Profile  Visit RBrian's Homepage  Reply with Quote
Since this thread has come to the top I'll follow up on the topic. We have decided to stay away from disc brakes. Have had several calipers locked up on the 2014's also. Another district in our area has installed exhaust brake switches on all of their disc brake buses. They say the brake wear should be greatly increased doing that. They tell me they expect to get up to 80,000 miles out of a set of pads. We did a pilot on 4 buses and its going well so yesterday I ordered those switches for the other 58 to put on the rest. When doing this you'll have to tweek the engine and bulk head modules software.




quote:
Originally posted by RBrian

Well we have been running 16 2012 buses with air disc brakes for 3 years, 23 2013's for 2 and 23 2014's over this last year.
Pros> Bus stops much better than drum brakes. Pads take 15 minutes to change out.
Cons> We're averaging 30,000 miles on the pads front and rear. Pads cost $200 not $80. Have had to replace 19 calipers under warranty. Calipers cost $1,000. Have had 10 LR calipers lock up. None on the right side. Wheel end gets so hot the ABS light comes on because the sensor is melted.

Bendix rep tells me that there was an "improvement package" that started in 7/2012 that should cure the issues with the caliper sticking. all our 12's and 13's were built before that. Have had no problems with the 2014 yet and pads do seem to be wearing better. Will have to wait another year and see what happens.









Edited by - RBrian on 02/23/2018 05:49:37 AM
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 02/23/2018 :  09:45:57 AM  Show Profile  Reply with Quote
I'm up to about 35,000 combined miles on the disks, smooth sailing so far. 2 more units being built Monday with them.

Learning curve for the drivers, you don't want to slap your foot on the pedal the way you are used to doing...but they love them.

Hopefully this time next year I'm not swearing out loud over them.
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RBrian
Senior Member

United States
71 Posts

Posted - 02/23/2018 :  10:09:03 AM  Show Profile  Visit RBrian's Homepage  Reply with Quote
I have read that doing this will also help keep the turbo in good working order.
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 02/23/2018 :  11:54:16 AM  Show Profile  Reply with Quote
I've wondered about the potential help the VGT brake give the turbo. Makes sense if it's forcing the vanes to move from one extreme to the other that it would reducing possibility of them sticking.

Turbo brake is not an option in my book, I require it on new buses.
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Kmiller
New Member

USA
5 Posts

Posted - 09/07/2018 :  03:29:23 AM  Show Profile  Reply with Quote
I have been dealing with the exact same problem with the Bendix Disc brakes. We have 317 (77 Passenger Bus) IC Conventional 2016-2018. So far we have roughly 50+ thermal overload occurrences. We have been working with Navistar/IC and Bendix for 6 months and they still have not found a solution. They have tested our buses at least 7-8 times. They have come out and placed sensors all over our buses to try and catch what is happening. Navistar/IC has even just recently shipped two of our buses to the Navistar proving grounds in Indiana to run testing. They still have no solution in sight. The best part is we are being told by Bendix and Navistar/IC that we are the only one having this problem. I did a search on the NHTSA website and found that in 2013 NHTSA did an investigation on this exact issue. Have any of you found a solution to this problem? Other than the Engine brake which I don't believe my county will want to install. How many others on here have had the same issue with LR disc brake thermal overload with the ABS sensor melting?
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 09/07/2018 :  09:15:23 AM  Show Profile  Reply with Quote
60,000 combined miles on them now, no issues to report. Hoping it stays that way.
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kummins
Active Member

41 Posts

Posted - 09/08/2018 :  06:52:41 AM  Show Profile  Visit kummins's Homepage  Reply with Quote
i know you said they're 'working' with you, but have they done any of these steps, including replacing the calipers? this is a known issue and i'd file warranty claims immediately.

here's the link to the procedures pdf, scroll down to item #BW7514 thermal overload checklist.

http://www.bendix.com/en/servicessupport/warranty/warranty_2.jsp


Edited by - kummins on 09/08/2018 06:56:07 AM
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Kmiller
New Member

USA
5 Posts

Posted - 09/10/2018 :  03:09:38 AM  Show Profile  Reply with Quote
Yes the first thing we did was the thermal overload check sheet. But we quickly figured out with Bendix that replacing the caliper was not the solution. Yes we have filed warranty claims. But they really don't know what is causing the thermal overload in the first place. It is a strange event even to them since it only happens on the LR on only our 77 passenger buses. We have 54 and 64 passenger buses and have never experienced thermal overload on them yet. They have replaced the calipers, rotors, sensors, service relay valves and some brake chambers on many different buses free of charge. They have sent us at least 13 free calipers. They have sent there air disc brake trainer to us for free. They are doing what they can but still can not pin point what has been causing this isolated thermal overload. The problem I have is both companies are claiming no one else is having this issue. But I don't believe that.
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 09/10/2018 :  03:35:07 AM  Show Profile  Reply with Quote
Just curious, are the brake chambers different between your 77 and the smaller units? I buy 78's, but have a 77-shell handicap bus which has a different size chamber (different axle rating). My rep told me that he's had a few issues with the size of chamber on my oddball.
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Bus Tech1
Senior Member

76 Posts

Posted - 09/10/2018 :  10:27:20 AM  Show Profile  Reply with Quote
We use the exhaust brakes and have seen 100,000+ miles on them (always depends on the driver and terrain). I have heard but do not know for a fact that the disc brakes are not getting the mileage that they thought they would on school buses.
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Kmiller
New Member

USA
5 Posts

Posted - 09/11/2018 :  08:48:46 AM  Show Profile  Reply with Quote
The brake system, components and layout are identical on all models and year of our 2016-2018 buses. So yes to answer your question the chambers are the same.
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Kmiller
New Member

USA
5 Posts

Posted - 09/11/2018 :  08:57:53 AM  Show Profile  Reply with Quote
We are using the standard brake pads on our buses currently and are getting anywhere between as low as 10,000 miles to as high as 35,000 miles. With that type of pad Bendix is claiming 35,000 is normal for the type of application. They recommended we switch to severe duty pads which are a harder compound and should extend our pad life. We are currently running a pilot on 15 or so of our buses to see how much improvement we can expect. I am interested in the exhaust brake and how it would help us but we have a lot of different routes and have a lot of stops close together so I am not sure how effective the exhaust brake would be.

Edited by - Kmiller on 09/11/2018 09:44:18 AM
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Thomasbus24
Administrator

USA
4544 Posts

Posted - 09/12/2018 :  07:42:19 AM  Show Profile  Reply with Quote
Keep us posted, please.
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RBrian
Senior Member

United States
71 Posts

Posted - 09/12/2018 :  2:08:31 PM  Show Profile  Visit RBrian's Homepage  Reply with Quote
quote:
Originally posted by Kmiller

We are using the standard brake pads on our buses currently and are getting anywhere between as low as 10,000 miles to as high as 35,000 miles. With that type of pad Bendix is claiming 35,000 is normal for the type of application. They recommended we switch to severe duty pads which are a harder compound and should extend our pad life. We are currently running a pilot on 15 or so of our buses to see how much improvement we can expect. I am interested in the exhaust brake and how it would help us but we have a lot of different routes and have a lot of stops close together so I am not sure how effective the exhaust brake would be.


It looks like we will double the life of the pads with the exhaust brake installed. Don't have numbers yet but it is looking very good. All our routes are city nothing rural here.
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