Air Disc -- Many out there?

This topic contains 14 replies and was last updated by chris-jodoin 12 years 7 months ago
February 5th, 2009 5:58am
Hey guys

Well tonight we had a Trimac trailer in and it had air disc brakes on it. This is the first one ive seen on a trailer. The lead guy at Trimac was telling me they just got 20 or so trailer with these but had to order them special.

Ive seen this setup on Firetrucks but thats it. Are you guys seeing these at all?
February 5th, 2009 6:05am
I'm seeing them regular now. And I like them. They are much easier to service. Get the literature, read up on them.

They will take over like they did with cars in the 70's. Soon you'll not see many trucks with drum brakes anymore.
February 5th, 2009 11:10am
February 8th, 2009 2:39am
I haven't seen them yet, but I have heard about air disc brakes before, and I think it would be a good idea to have a brakeing system that is quicker to mantain and service over the normal drum brakes.
February 9th, 2009 11:08am
Yeah it seemed to be quite serviceable. The Fleet manager was telling me they are getting 800 000k on a set of rotors. And thats on a trailer with a broker pulling it!
February 10th, 2009 6:03am
europe has been using air disc brakes with abs for about 10 years or so.on trucks,trailers, and buses. the big users are mann & merc. in canada there mostly used by pervost & mci buses. when adjusting the brakes. be carful not to over torque the adjuster or it will brake off.i should know.i did it twice.
February 10th, 2009 3:57pm
The ones that I work on are on Nova Bus, which is now owned by Volvo. I also think that Prevost, the previous owner of Nova was also bought out by Volvo.

And yes you have to be careful of the shear nut, but that's why it's there, to prevent overtorquing while backing off or adjusting the calipers. New ones come with the linings, and it's a good idea to keep some of the old ones in your box for backup should any break.

November 5th, 2009 6:44pm
Yes 50% of the trailers we see are air/disc. So much easier to overhaul brakes and they seem to have better performance and last longer than the drum type.
November 5th, 2009 10:45pm
If you like these you'll love the next generation. The current models are basically the European version. European trucks don't typically use anti-compounding. This means the current model is way heavier than a North American truck needs. The newer light weight version will have the rotor splined onto the hub instead of bolted to the back as they currently are. A tool with points on it will be inserted in place of the pads. Step on the brake pedal and the rotor will crack. Rotate the rotor 108deg and apply the brakes again. The rotor will now be cracked in half and slip right off. The new rotor will be pre-broken (much like a cracked rod). Slip it in place and bolt it together. Done. You won't have to ruin a perfectly good wheel seal and you'll be able to do the whole truck in less time than it took to do one wheel end :woohoo:

Another handy hint team a disk brake up with super single tires and the caliper will stick out far enough that you don't even have to jack up the truck to change the pads :cheer:
November 27th, 2009 3:37am
Are we talking about air-actuated caliper brakes on trucks? Yeah, I have them here in Saudi, The Mercedes Actros have them in all wheels, while the MAN Trucks have them in front wheels only. Yeah, replacing of brake pads is easy... shear nuts? are those the little sockets wrenches provided in new set of brake pads? now I'm aware why they are thin.. designed to break to prevent over-torque.. thanks for the info buddy..
December 3rd, 2009 2:16am
We have over 500 2006 53' trailers with disc brakes on them as part of our fleet. Overall the principal is great and the cost savings potential is terrific. However, due to issues with siezed calipers (and the subsequent rotor damage) it may be difficult to justify going with disc until the problem with the siezed calipers is overcome.

Here is some general cost info:

upcharge from manufacturer per axle-$1000 ($2000/trailer, $1 000 000 overall)

caliper-$800 ea

rotor-$400 ea

padset-$200 ea

labour is estimated at 1.5/wheel end (including torque)
December 3rd, 2009 12:34pm
mpoland wrote:


We have over 500 2006 53' trailers with disc brakes on them...(major clipage)...labour is estimated at 1.5/wheel end (including torque)

Who's brakes? Wabco or Bendix? I haven't heard of the sticking issues. Bendix is practically giving theirs away (just to get them out there) to big fleets so if they are savvy with their purchase money shouldn't be a issue.

What does that labor include? If were talking rotor replacement I might buy that as the rotor is currently inboard of the hub. Under normal circumstances the rotor shouldn't have to be replaced every time and changing the pads should take about 20 minutes. (including wheel torque)
September 11th, 2010 11:16pm
October 10th, 2010 6:53pm
Hi -

We have a crap load of these on fleet and have done since 1999. As some have stated, dont need much maintenance, but the little that they do is very important. We closed our workshop in 2003 and had nothing but problems with certain brakes we had on fleet due to the wrong maintenance. Coupled with EBS and antiroll technology (Escpecially on our double deck fleet of trailers) they are great pieces of kit.

The 3 we use -

ROR Meritor DX195 - these are a pig. ROR finally worked out after flooding the market with a cheaper disc (rotor) that the lack of a grease nipple on the sliders was resulting in calliper failure. Any re-manufactured callipers have this fitted now. Due to this massive failure many UK transport companies moved away from disc back to drums.

BPW - Not a bad axle/brake set up... a middle of the road set up without many problems at all.

DC - Daimler Chrysler - Mother of all discs. We have a few trailers on this. Fitted to the Mercedes benz LGV's, built for tanks. Awesome kit. We do pay a little extra up front, but this has proved to be well worth it 4 years in.

Adjusters - you can buy the adjuster sockets for the adjusters. These snap at a pre-determined torque so you cant damage the adjusters.

Maintenance, typically we are re-padding every 2 years, discs are lasting 4/5 years. Though we have suffered with excitor ring failure due to rust closing the gaps. All of our trailers are tri axle with EBS sensing off the centre axles. Running at about 79000 kms a year.

As for the tractor units, all are now disc all round. We operate Scania and MAN 6x2 with centre lift axles.

Still have problems with callipers on the MAN. Though hopefully they will be all gone next year - thank the lord.
December 28th, 2010 5:35am
in north america they are common on highway coaches like prevost, setra, mci, and vanhool just to name a few. The first disc brakes that were availble were solid rotors. The buses that they were equipped had all three axles with rotors or only on the steer and tag axles. Now those are equipped with rotors on all of the axles alongside with abs. But serviceablility is very simple the adjusting socket comes in a box of pads. If you put too much torque on the socket it will break.

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