Should Truck Drivers Be Using Air Disc Brakes?

Are truck drivers looking for ways to decrease maintenance burden? Sure, we can talk all day about tires and driving habits, but have you taken a second look at your brakes? The fact is, the right air disc brake (ADB) spec could put an end to your brake maintenance woes for good.

We all know that better stopping power is usually the most touted advantage of air disc brakes, but the fact is, advanced drum brakes can easily meet the requirements as well. Where air disc brakes pull ahead is in the area of simplified maintenance requirements. Let’s dig a little deeper.

The ADB Advantage

Believe it or not, in a typical long-haul application, a fleet technician might never have to do maintenance on an ADB over the lifetime of the tractor. Considering ADB rotor life is around 700,000 miles and pads around 400,000 miles, if you spec your ADB right, you may not have to deal with regular brake maintenance – other than inspections, of course. So as long as you don’t have to change the rotors, you can expect lower maintenance costs and reduced overall cost of ownership.

Also bear in mind the inherent cost in maintaining drum brakes. A routine reline service on a drum brake can run into an hour or more per wheel-end, a pretty penny when you are paying the technician.

Conversely, changing a pad on an air disc system can be done in as little as 20 minutes. In some cases, you may not even have to remove the wheel. While rotor and drum changes are a bit more complicated, it’s usually likely that the initial truck owner won’t need to change a rotor over the truck’s lifetime.

So in reality, outside of pad changes, most ADB systems would likely be able to go through a fleet trade cycle without ever needing any serious maintenance. Now that’s some serious cost-stopping power!

What About Premium Drums?

While many can point to premium drum installations as being as relatively pain-free as their ADB counterparts, there are more parts to a drum system that will require periodic maintenance. Keep in mind that brake adjusters will need periodic lubrication, clevis pins will need to be monitored for free movement, and linings and drums inspected for cracking or expansion of the linings.

With ADB brake systems, you won’t have to worry about any of that. Does that mean ADBs are completely pain-free? No. One potential problem could be water intrusion around the piston seals and calipers. But while ADBs aren’t completely trouble-free, they certainly require far less maintenance than their drum counterparts.

The fact remains: Drum brakes, although reliable, are put out-of-service 20 percent of the time, with most being adjustment related. It’s a problem you simply don’t have to worry about with disc brakes.

Other Advantages

Still, there are even more advantages to going with disc brakes. One is in the area of roadside inspections. While this may change in the future, today there really isn’t a good way to do a roadside inspection of disc brakes.

Since the adjustment mechanism is internal to the brake, it isn’t susceptible to manual inspection. So as long as the brake caliper is in good working order, there is little chance for a failed brake inspection. And since disc brakes are generally more reliable, this could mean less hits for a motor carrier’s score under the Compliance, Safety, Accountability (CSA) program.

Another advantage lies in servicing costs. Disc brakes take significantly less time to repair than drum brakes. Once the wheel is off, a pad reline should take only a few minutes.

So next time you are looking at truck specs, keep your brakes in mind. In the end, opting for ADBs could save you big over the figurative, and literal, long-haul.