Air Brakes

We stand in front of our brake jobs!

  • » Stressed about maintaining the touchy air brakes of your fleet?
  • » Worried about jackknifing your trailer?
  • » Need a timing test on your air brakes to satisfy federal regulations?

Contact Vancouver Axle for air brake service in the Fraser Valley, BC!  We are federally authorized to perform air brake timing tests.  See us to certify the safety of your vehicle with Transport Canada’s National Safety Mark (NSM). When it comes to your air brakes, REGULAR maintenance DONE RIGHT is essential for safety and to meet regulations!  Contact us now to schedule air brake services!

Basics of Air Brakes

As drivers of heavy-duty vehicles know, air brakes don’t work instantly like hydraulic brakes.  With compressed air brakes, air needs to flow through your brake lines before you can brake.  This means you must allow for about one-half second or more delay in your braking time (and that’s in perfect conditions with brakes in excellent shape).

When you use air brakes, variables such as road conditions, season, driving behavior, type and frequency of inspections, among other factors all play a part in a delicate balance.

Some CDL training manuals claim that air brake lag distance at 55 mph on dry pavement adds about 32 feet.  That means, if you’re driving your rig at 55 mph with good traction and good brake conditions, the total stopping distance is more than 300 feet or 100 yards (think of the stopping distance of a football field…without the end zone length).

Air brake systems include numerous parts that need care: Control pedals, parking brakes, service brakes, an air compressor, and a compressed air storage tank, to name a few.

AIR BRAKES WORK HARDER IN AN EMERGENCY!

Even poorly-maintained air brake systems will offer lower-level braking force to “get by” and stop/slow your vehicle in normal conditions.  But, in an EMERGENCY, air brakes must WORK HARDER than hydraulic brakes to be ready for stopping! In an urgent situation, if you apply neglected air brakes—hard—you won’t get the quick deceleration you need.  This could cost you your business…and worse.

Are your air brakes out of balance?

Torque imbalance:
Occurs when there is a mismatch in the amount of work done between your tractor brakes and trailer brakes.  In a complicated air-brake system, all of your brakes’ temperatures should be within 20 degrees F of each other. Air brakes are designed to work with the maximum capacity of your axle, so the load you’re carrying can affect torque balance, too. An empty or partially loaded rig can cause an imbalance in your brakes.  The brakes on some of the wheels will do more of the work and make them more prone than others to locking up. Torque imbalance can lead to jackknifing and trailer swing-out.

Pneumatic imbalance:
Happens when the air pressure and timing are out of balance in the brakes between your tractor and trailer.  Brake engineers generally recommend no greater than a 2 psi difference for a 20-psi brake application.  Any greater difference in pressure will mean your brakes are not being applied equally.  If the braking of your tractor and trailer is out of sync, your trailer may end up pushing and jackknifing your tractor.

For proper maintenance of your fleets, replace brake valves and brake linings with products that perform identically; brake values should offer the same crack pressures and brake linings the same friction levels.

Prevent jackknifing and trailer swing-out and CONTACT US NOW for regular air brake maintenance DONE RIGHT! 

Air Brake Timing Tests

We are federally authorized to perform air brake timing tests.  See us to certify the safety of your vehicle with Transport Canada’s National Safety Mark (NSM).  Our test captures air brake events for timing, application, release, recovery or balance. We will also test for pressure balance, differential, and leak type tests.

  • Certify truck or trailer air brakes to meet Canadian CMVSS 121 requirements
  • Brake tests can be run for vehicles independently or in tandem, such as a tractor-trailer brake test combination
  • Accurately test up to 18 positions simultaneously on 9 axles
  • Alerts for balance to eliminate trailer over-ride

Other air brake problems

Water in air brake system:
Modern air brakes are equipped with water drain valves to keep water out of the air brake system.  However, in older vehicles or in vehicles with malfunctioning valves,water can find its way into air brake lines and cause serious trouble.  In cold weather, ice can form and block air from passing into the brake lines.  This may cause your wheels to lock up.

Worn rubber seals on air couplers:
Worn seals can allow air to escape from the system; wheels can lock up as a result.

Change Your Driving Behavior to Preserve your Brakes

Avoid any behavior that may cause you to slam on your brakes.

Brake with your engine, not just your brakes.
Brakes by design can take a lot of heat.  Still–get in the habit of using your engine to slow your vehicle.  Air brakes can deteriorate and even fail when you rely too heavily on them alone.

Don’t tailgate.
Allow for the unexpected with extra stopping distance.  Remember, you have air brakes, not hydraulic brakes.

Don’t ride the brakes:
Keep in mind when going downhill.

Don’t drive too fast:
The late comedian George Carlin once joked, “Have you ever noticed when you’re driving that anyone who’s driving slower than you is an idiot and anyone driving faster is a maniac?” Strike a balance between these two extremes.